If you are going to write about something you have done, tested or investigated, do not wait until the writing stage to think about evidence.
By then, some of the most useful proof may already have disappeared.
The dirty sink has been cleaned.
The garden hole has been filled.
The error message has vanished.
The product has been assembled.
The original settings have been changed.
You may remember what happened, but you can no longer show it properly.
An evidence portfolio solves this problem.
It is a planned collection of photographs, videos, screenshots, notes, measurements, source material and other records gathered before and during the activity you intend to write about.
The purpose is simple:
To make sure you can show what you did, explain what happened and support the claims you make in the finished article.
Why an Evidence Portfolio Matters
It is easy to tell readers that you tried something.
It is more convincing when you can show them.
Suppose you write that:
- the ground was unusually hard to dig;
- limescale came away from a tap after several minutes of scrubbing;
- one telescope mount was easier to use than another;
- a piece of software produced an error;
- a particular route took longer than expected;
- or a product worked differently from the manufacturer’s description.
Each statement becomes more useful when you have evidence to support it.
That evidence does not merely make the article look more trustworthy. It can also help you remember details, notice patterns and reach a more accurate conclusion.
Instead of writing the article you expected to write, you can write the article that the evidence justifies.
What AI Mode Suggested
As part of researching this topic, I asked Google AI Mode three differently worded questions about collecting evidence before writing a blog post.
The first answer produced a broad checklist. It recommended photographs, videos, timestamps, measurements, primary sources and disclosures.
The second became more formal. It introduced ideas such as a “chain of custody,” continuous video, image metadata, public datasets and independent verification.
The third suggested a complete planning system involving:
- an outline created in advance;
- an evidence-capture spreadsheet;
- numbered storage folders;
- standard file names;
- automated screen recordings;
- and mandatory pause points throughout the project.
Some of this advice was useful.
Some of it was excessive for an ordinary hobby website.
More importantly, the detailed recommendations were often only loosely connected to the cited sources. The answers sounded authoritative, but the supporting pages did not always establish the specific methods being recommended.
That revealed a useful gap.
The goal should not be to collect every possible form of evidence or make an ordinary blog post resemble a forensic investigation.
The goal is to collect the right evidence for the claims you are likely to make.
Start With the Question Your Article Will Answer
Before beginning the activity, write down the question you hope the eventual article will answer.
For example:
Can Viakal remove the visible limescale from my bathroom sink using only a microfibre cloth?
That is more useful than simply deciding to write an article about cleaning a sink.
A clear question helps you identify:
- what the starting condition must show;
- what process needs documenting;
- what result matters;
- what measurements might be useful;
- and what limitations should be recorded.
You do not need to know your final conclusion.
In fact, you should not decide it in advance.
You are only defining what you are trying to find out.
Anticipate the Claims You May Need to Support
Next, think about the statements the eventual article may contain.
For the sink-cleaning example, these might be:
- The sink had visible limescale before cleaning.
- I used Viakal and a microfibre cloth.
- I left the product on for a particular length of time.
- Some areas required more scrubbing than others.
- The visible limescale was reduced.
- The entire task took around 15 minutes.
Each possible claim suggests a form of evidence.
| Possible claim | Useful evidence |
|---|---|
| The sink had visible limescale | Clear photographs before cleaning |
| These were the products used | Photograph of the products and tools |
| The product was left for five minutes | A written time note or short video |
| The limescale required scrubbing | Video showing the cleaning process |
| The appearance improved | Comparable before-and-after photographs |
| The job took 15 minutes | Start and finish times |
| The product is suitable for the surface | Manufacturer guidance |
You do not need to write the full article before doing the activity.
You only need to think far enough ahead to avoid missing evidence that cannot be recreated.
Identify the Moments That Will Disappear
Some evidence can be captured later.
Some cannot.
You can photograph the cleaning product after the sink has been cleaned.
You cannot recreate the original condition of the sink once the limescale has gone.
This means your evidence plan should identify irreversible moments.
These might include:
- before opening a package;
- before assembling a product;
- before cleaning or repairing something;
- before changing a software setting;
- when an error message appears;
- when something breaks;
- when an unexpected result occurs;
- before leaving for a journey;
- before changing the testing conditions;
- and immediately after completing the activity.
These are the moments when it is worth pausing briefly and documenting what is in front of you.
Capture Generously, Publish Selectively
My own approach is simple:
Take loads of pictures.
Mobile phones make this easy. There is little cost to taking more photographs than you eventually need, and you can delete obvious duplicates later.
Take:
- wide shots showing the overall situation;
- close-ups of important details;
- before photographs;
- photographs during the process;
- after photographs;
- pictures of tools and products;
- screenshots of settings;
- mistakes and failed attempts;
- unexpected results;
- and alternative angles in case one image turns out to be unclear.
You may not know which photograph will become important until you begin writing.
A small detail in the background might later explain why something happened.
A close-up you thought was unnecessary may become the clearest proof of the result.
A photograph of an unsuccessful attempt may make the article more helpful than the polished final image.
The principle is:
Capture more than the minimum, then use only what helps the reader.
Minimum sufficient evidence should apply to what you publish, not necessarily to what you collect.
Do Not Be Afraid of Raw Photographs
Image quality matters, but evidence does not always need to look professionally staged.
A slightly rough photograph taken halfway through a job can be more useful than a perfect photograph taken afterwards.
The reader may need to see:
- how muddy the working conditions were;
- how awkward the space was;
- how much limescale remained;
- how the parts fitted together;
- how damaged something looked;
- or where the process started to go wrong.
A raw photograph can preserve the reality of the situation.
That authenticity may be more useful than a carefully arranged image with perfect lighting.
This does not mean any photograph is good enough.
The subject should still be visible and understandable.
But do not confuse imperfect evidence with poor evidence.
Poor evidence is unclear, misleading or unrelated to the claim.
Imperfect evidence may be unpolished while still showing exactly what happened.
Record Short Videos as Well
Video can capture things a photograph cannot.
A photograph may show a clean tap.
A video can show whether the limescale wiped away immediately or required repeated scrubbing.
A photograph may show a completed garden hole.
A video can show how hard the ground was and how much effort it took to break through it.
A screenshot may show an error message.
A screen recording can show the exact steps that caused it to appear.
The video does not need to be cinematic.
A short handheld phone recording may be enough to capture:
- movement;
- sound;
- resistance;
- speed;
- timing;
- effort;
- or the sequence in which something happened.
The aim is not to produce a television programme.
The aim is to preserve useful information.
Record the Messy Parts
Do not document only the successful moments.
Capture:
- mistakes;
- failed attempts;
- changes of plan;
- unexpected costs;
- confusing instructions;
- broken parts;
- poor results;
- and moments when your original assumption turned out to be wrong.
These details often become the most valuable parts of the article.
Anyone can repeat the ideal process described in a manual.
The person who has actually done the task can explain what happened when reality did not follow the instructions.
A mistake may reveal:
- what readers should avoid;
- which step needs more explanation;
- where a product is difficult to use;
- or why a seemingly simple task takes longer than expected.
Do not tidy the story so thoroughly that all the useful experience disappears.
Keep Simple Notes While You Work
Photographs and videos may not capture everything.
Keep a basic note on your phone or in a notebook.
Record details such as:
- start and finish times;
- measurements;
- product names;
- settings;
- weather conditions;
- costs;
- unexpected observations;
- questions that occur to you;
- and anything you may struggle to remember later.
These notes do not need to be polished.
A line such as:
10:35 — first spray removed some surface marks, but heavier limescale around the base still needs scrubbing
may be enough to preserve an important detail.
Contemporaneous notes are usually more reliable than trying to reconstruct the process several days later.
Capture Context, Not Just Proof
Evidence can still mislead when important context is missing.
A before-and-after photograph may show an improvement, but readers may also need to know:
- how long the task took;
- how much product was used;
- whether several attempts were required;
- whether the lighting changed;
- whether the item was moved;
- whether another method was also used;
- or whether the result was temporary.
The goal is not merely to prove that something happened.
The goal is to help the reader understand how and why it happened.
This is especially important when comparing products or methods.
If two products were tested under different conditions, the comparison may not support the conclusion you want to make.
Record enough context to explain the limitations honestly.
Match the Strength of the Evidence to the Claim
Not every article needs controlled testing, spreadsheets or forensic metadata.
The level of evidence should be proportionate to the claim.
For example:
This product removed the visible limescale from my tap.
A clear before-and-after photograph and a description of the process may be sufficient.
But this is a much broader claim:
This is the most effective limescale remover available.
That would require a fair comparison across several products, consistent testing conditions and clearly defined measures of effectiveness.
The stronger the claim, the stronger the evidence needs to be.
This leads to an important rule:
Do not make the claim broader than the evidence allows.
Your personal test can establish what happened during your test.
It may not establish what will happen in every home, with every surface, under every set of conditions.
Imagine the Judge Saying: “Prove It”
A useful way to plan your evidence portfolio is to imagine that you are standing in a courtroom.
You say you cleaned the limescale from the taps.
The judge says:
“Prove it.”
You say the ground was unusually hard to dig.
The judge says:
“Prove it.”
You say one product worked better than another.
Again, the judge says:
“Prove it.”
This does not mean you need legal-grade documentation.
The imaginary judge is not demanding a formal chain of custody, continuous filming or forensic analysis.
The question simply forces you to consider whether you have enough evidence to support what you are saying.
Can you show:
- the starting position;
- the tools or products used;
- the process;
- the difficulties;
- the result;
- and how you reached your conclusion?
Compile enough evidence that a reasonable reader can follow what happened.
Organise the Material Without Making It Complicated
Your evidence portfolio does not need an elaborate system.
For a small project, one folder may be enough.
You might create simple subfolders such as:
- 01 Before
- 02 Process
- 03 Problems
- 04 Results
- 05 Notes and Sources
For a digital project, you could use the same structure for screenshots and screen recordings.
Rename only the files that need explanation.
The purpose of the system is to help you find the evidence later, not to create extra administration.
A complicated evidence system that interrupts the activity may do more harm than good.
Use the simplest structure that prevents important material from becoming lost.
Separate the Portfolio From the Finished Article
Your evidence portfolio will usually contain more material than the article needs.
That is normal.
The raw portfolio might include:
- 40 photographs;
- several short videos;
- rough notes;
- screenshots;
- receipts;
- measurements;
- source links;
- failed attempts;
- and abandoned ideas.
The final article may use only six photographs, one video and a few key observations.
The reader does not need to see every piece of evidence.
They need to see the evidence that helps them understand the process and evaluate the important claims.
Think of the portfolio as the complete record and the article as the carefully selected presentation.
Audit Your Evidence Before Writing
Once the activity is complete, review the material before drafting the article.
List the main claims you expect to make and ask:
What evidence do I have for this?
There are three possible answers.
The evidence supports the claim
Use the strongest and clearest evidence in the article.
The evidence partly supports the claim
Narrow the wording.
Instead of saying:
The product removes limescale easily.
You might say:
In my test, the lighter marks came away quickly, although the heavier deposits required repeated scrubbing.
The evidence does not support the claim
Remove it or perform further testing.
Do not use weak evidence to decorate a conclusion you had already decided to make.
The evidence should help determine the conclusion.
A Simple Evidence Portfolio Checklist
Before starting:
- Define the question the article will answer.
- List the main claims you may need to support.
- Identify the moments that cannot be recreated.
- Prepare your phone, camera, notes or screen recorder.
- Record the starting condition.
During the activity:
- Take plenty of photographs.
- Record short videos where movement or effort matters.
- Save screenshots and error messages.
- Note times, measurements and settings.
- Capture mistakes and unexpected results.
- Record changes to the original plan.
Afterwards:
- Photograph the final result.
- Save relevant receipts, sources and instructions.
- Organise the material into a simple folder.
- Compare each likely claim with the available evidence.
- Narrow or remove claims that the evidence cannot support.
- Select only the most useful material for the article.
The Principle to Remember
An evidence portfolio is not just a folder full of photographs.
It is the connection between doing the work and being able to write accurately about it later.
Plan the evidence you know you will need.
Take far more photographs than you expect to publish.
Record raw, authentic moments even when they are not visually perfect.
Preserve the mistakes as well as the successes.
Then imagine the judge looking at every important claim and saying:
“Prove it.”
You can delete an unnecessary photograph later.
You cannot return to an earlier stage once it has disappeared.
Capture generously. Publish selectively. Let the evidence determine what you can honestly say.