This is the easiest and simplest hairdo you could do with your hair.
Using an old curl set, braid out or twist out. Gather all your hair fairly close to your face. Using any wrist size non abrasive hair tie flip it around your pony tail only once. Now adjust your hair. Push, pull, tuck and move around and you are done.
You can even move the bun over to one side for some variation.
This is my go to choice hairstyle for a lazy day. Whats yours?