You must show her that you are truly sorry and that you want to rehabilitate in front of her. You have to behave in this way.

Depends on how much of a boneheaded thing you did. Roses are good in general and a 'sorry' only works if you are truly sorry.

If you made a really big mistake, I am sorry it is just can not make up for, but if they are small errors, a sorry, a hug, a kiss, can be forgiven her!

ooh, you made a girl mad? BIG mistake...you know she's never going to forget that? tell her not just sorry, but "I WAS WRONG." this will make her happy because women love to be right :)

Yeah better admit that you were wrong but add looking really sad and depressed into it. Might cause girl in guestion to be merciful to you but don't overdo the "looking pitiful" part because if you look too sad and depressed that might rouse the little inner bitch inside her...