Report writing is something I do a lot, but I don't usually think about how to do it. After being asked to give a presentation about report writing, I started noticing what I do. Every report is different, but here are my basic steps.
1. Access the content
Ideally talk to an expert on the subject. Find the relevant written information and read it through, marking up what's likely to be important.
2. Write a structure
Many organisations have a template for their reports. If there isn't a standard structure, spend some time identifying headings under which to group the information, and number the headings in the order you think they need to be in. Read over your content, and match it to the relevant heading number.
3. Fast, free flow writing
Write the report in one go, without stopping to check things or perfect sentences. At this stage it's all about getting the information down. Often the writing experience is quite uncomfortable at this stage because you will feel like your are making stuff up, but stick with it. It's amazing how much of this first draft turns out to be worth keeping.
4. Respond to what is on the page
This is the stage where finding a quiet place to read through the draft is valuable. This stage is far more about the meaning of the report than the individual sentences. It's having your radar on, and going slowly, checking anything that doesn't seem right or is missing, and making substantive changes - both additions and subtractions.
5. Slow polish
This is the luxurious stage. The report's message is in place. Now it's just about making each sentence read well. It's the time to pick up typos and improve sentence structure. It's the easiest step of the whole process, but it adds to the professionalism of the report. It's ideal to do this one more time than you think you need to (or want to!). Where possible, if the deadline isn't too tight,take a break between the last two reviews to refresh your mind, so it's easy to spot those very last, minor changes.