Depending what you want to study, the information that you want to show, you have to use different scales, different colors. For example the first drawing is about a part of the city, you can't see the people, because is very small, but you can see the public or the private spaces. In the second one is a block of flats, and you can study the people that appears in your space, I mean, the red dots are people that you know, and blue dots are people that you don´t know. In the third one you can find a drawing about my house with the different spaces. the colors show the privacity: more red, more private.