i wear a bun with added hair around it. To prep during wash day I usually wash and then put in medium two strand twists, and ponytail them to stretch the hair while it airdrys, then I wear a wig cap over it every night to get the flyaways to lay flat, then when I take my hair out of the twists the day after my wash day I smooth it with my hand into a ponytail, twist the ends of my ponytail and tuck them into the ouchless ponytail holder, then using kinky curly fingercomber hair I wrap it around my bunnytailed hair and pin it with hair pins, not bobby pins to keep it secure.
Then at night I take the pins off and added hair off and keep my ponytailed hair up and sleep with the wig cap on and a scarf to keep all edges smooth. Occasionally i will spray with leave-in or water and smooth out and then put the wig cap on to keep my hair stretched and flat. That usually lasts a whole week and then i wash and repeat on wash day.
ETA: Picture #2 is of just my hair and how I two strand twist the hair in the ponytail and then tuck the ends in the holder to make a baby bun. The rest are of different days with me wearing the bun