When I first started doing design observations, there was ABSOLUTELY no structure. I just went ahead to observe the surroundings and talking to as many people as I can. Although I did get some insights from this process, I realised that there could be a better way.
There are three major steps you could follow. Step 1 — Noting down the key assumptions concerning the user. Listing them down beforehand tells you how right/wrong you were about the user.
Step 2 — List down the category buckets. For example, while designing for the public healthcare space, I noted down the category buckets as — people, infrastructure, technology etc. This could vary according to the context of your problem space.
By listing down the category buckets, you prime your mind to think more consciously about them.
When in doubt figuring out the category buckets, you could also follow the AEIOU Framework. In short, A = Activities E = Environments I = Interactions O = Objects U = Users
In my current work designing for the public healthcare space, A = Activities (Daily doctor rounds etc) E = Environment (Maternity wards etc) I = Interactions (Nurse checking vitals of patients) O = Objects (Posters, Placards) U = Users (Senior doctors, Paediatricians etc)
The AEIOU Framework can also be downloaded and printed in a fun and engaging way to be used — Source: Open Practise Library
Once the observations are done, it's advisable to process all your scribbles, sticky notes and field notes in one place. Best time to do this is when your memory is fresh. Process and collect them together. This is where the cream of the cream lies — your UNIQUE INSIGHTS
To summarise —
1. Note down key assumptions
2. Use the AEIOU framework to make categories of your observations
3. Process and bring together all your field notes on the very same day
4. Reflect and revisit on your assumptions