To be completely honest, doing my hair is not my thing. I can get it took look pretty good most of the time. I don't do anything too complex though, and I rarely try anything new. So basically if I can do this anyone can.
First brush or comb your hair straight back.
Take a section about three to four inches wide in the front middle and about two inches deep (the top front middle of your hair)
Split it in three and braid neatly while holding it back so it will lay flat against your head without bumps
Braid about six inches. Secure end with small elastic or bobby pin/clip (this is just temporary)
Put hair including braid into a high pony
Remove elastic, clip, etc from end of braid
Twist hair into bun and secure with elastic or pins (I tuck the end into the elastic of my pony)