I have long hair. It can get in the way. Consequently, I keep my hair up in a french braid much of the time, and also braid it each night before bed to reduce tangling.
I've made a couple of approaches to this: I have this video, below; I have a Pinterest-style series of pictures on the first step; and I've done a step-by-step. If I were you, I'd start with the video. It gives the fullest picture. But if you need more help, the step-by-step is worded a bit differently.
I'd love if you'd comment on this to tell me which approach is most useful (or if I should keep trying several ways to do it). And of course, if you have any questions or clarifications, I respond to comments!
The video below is an overall lesson and demonstration, with voiceover and captioning:
If you need more help, continue on to read the step-by-step!
Step 1: Get a Bit of Hair From Each Side of Your Head