Reddit reviews Goody Hair Simple Styles Mini Spin Hair Pin, Great for All Hair Types, Colors May Vary, Pack of 3 Pins

I have really long, thick hair and do a braided bun. It sounds complicated but is easy (if you know how to braid) once you get used to it. In high school I did it every day during my alst class to get ready for softball practice, and it stayed without issue for practice, games, etc., even with putting on and taking off my helmet.

1. Braid hair into two french braids (like pigtails)
   
   
2. Rubberband the pigtails together in the back of your head, wherever you want your bun to be (low-ish usually works for me, but not so low that it's on my neck)
   
   
3. one at a time, wrap the brainds around the center rubber band to make a bun.
   
   
4. secure with 2 (or 3) more hairties OR use these awesome "swizzle sticks" (I usually do this when I'm wearing this in my regular life as a "hair-do" vs for exercise
   
   (Here'sa time I wore this to a wedding, though in this pic it's one french braid down the back, pony tail at back of head, two regular braids from the loose hair, and the continue steps 3&4 )

my mom has thin hair and uses the three piece ones. they are a bit smaller and the third one helps secure the bun better!

like this :)