I have not counted the number of sketchbooks that I have full of these things. I do them when I sit on the couch after a long day. It helps me to relax, but I have never really done it in a structured way. It’s really whatever comes to me. I might make a grid one day and swirls another day. I might chose one or two patterns to fill my whole page.
Or maybe just a whole bunch of versions of the same thing.
My object is just to keep my mind and my hands busy doing something. It is very relaxing for me. Purists of zentangle say that you have to create with purpose so that your mind is occupied by something other that thinking. Your supposed to be focused on what you are doing. Part of me is, but part of me is talking to the people around me or catching up on the news.
For me it is having the desired affect, and maybe I am doing it write. Either way, I enjoy it a lot and have come up with some pretty amazing designs. I have the sketch books to prove it!