Make her feel wanted: Chasing after your partner, complimenting and acting as if you are trying to get them to bed for the first time every time is sure to boost their interest in you and having sex.  This is also a great confidence boost, and confidence feels sexy.  This gives both of you a chance to build anticipation and prepare for sex mentally. Exchanging glances, kisses and touches, then teasingly walking away can help the increase the intensity of what is to come.