ok when my hair was long i had very many ways to do my bun but i found the perfect way

1. pull oyur hair back in a secure pony tail
2.divide it into two peices
3. wet each one woth water
4. take one of the peaces and wrap it around the pony tail as you are wrapping stick bobby pins in there
5. do the same on the other peice of hair but go the ohter way
6. then if you have any sgraggly hairs just put a hair net over it or spray it

and this will make a flat secure bun

xoxo good luck