The short answer
A client report answers three questions: what did you do, what happened to the numbers, and what comes next. Link each piece of work to the page it touched and the period you measured, state how much data stands behind a change, and say plainly when a month was flat or when the cause is unclear.
Start from what the client needs to decide
Most clients do not read a report for its charts. They read it to decide whether to keep paying, whether to spend more, and what they have to do themselves. A report built around those decisions is shorter than one built around every metric you can export.
Put the answer on the first screen: traffic compared with the previous period, the two or three pieces of work that matter, and what you propose next. Everything else is reference and can sit below it.
Tie each piece of work to a page and a period
A list of tasks completed is a list of activity. A client can see activity is not the same as progress. For each piece of work, name the page, say what changed, give the date, and show the same metric before and after for that page.
That structure also protects you. When a month is down, the report shows which pages moved and which did not, instead of one site-wide number that nobody can act on.
- The page and what you changed.
- The date, so the before and after periods are clear.
- Clicks per day before and after, for that page.
- How much data the comparison rests on.
Where the evidence stops
Say how sure you are
A client who sees a percentage will treat it as a fact. If the page had a few dozen impressions, the percentage is mostly noise. Mark such results as tentative, or leave out the percentage and say that there is too little data to tell.
Do the same for other explanations. If you changed two things on a page in the same month, or the whole site moved together, say that the result may not come from one edit. A client who learns this from you trusts the numbers you do stand behind.
Report a flat or falling month honestly
Every account has them. Name the drop, say what you checked, and separate what you know from what you suspect: a seasonal dip, a change in the results page, a competitor, a technical fault. Then say what you will do next and when you will look again.
A report that only ever goes up gets read as marketing. A report that explains a bad month gives the good months their credibility.
Keep the structure the same every month
A client learns where to look when the report has the same order every month: summary, work done, measured results, what is open, next steps. A new layout each month makes them hunt for the number they care about.
Keep an archive. Being able to open the report from six months ago and see what was promised, what was done and what moved is the simplest answer to the question of what they are paying for.
What not to put in
Leave out metrics that move without meaning anything to the client, such as a visibility index with no link to visits, and rankings for terms nobody searches for. Leave out claims of cause that you cannot support. If you cannot show that your change produced the difference, report the difference and the change next to each other and let the wording stay at that.
In Lastmod
Lastmod writes a monthly report per website with open work, finished tasks and measured results, each with how reliable the measurement is and a mark where other changes may explain it. On the Agency plan the report carries your name, logo and commentary. It states what changed between two periods; it does not claim your work caused it.