- Do stuff she (and you) likes; going out, dancing, hiking, whatever. Don't do it too often though, but when you do, make it special.
- Experiment in bed; different sexual positions, anal (if she wants to), keep her satisfied in bed - don't always come before she does or has multiple times.
- Keep teasing her.
- Always stand up to her if you feel you should.
- Tell her when other women flirt with you (works like a charm for me, she knows she has a popular boyfriend, but SHE has the prize).
- Ask her for advice when you get your hair cut/go shopping. It doesn't hurt to do some things to yourself/wear stuff that she finds attractive, and she will do the same for you. (I grow my hair long, she got her bellybutton pierced.)
- Hang out with your friends, have other hobbies/activities that don't involve her.
Thats about it, taken from my own experience
Chillburg