How to rid of the shyness in bed (not being sick minded)?

Im not trying to sound sick. When it comes to bed/sex Im sooo shy about taking over. My husband wants me to be in charge and to dress nice. Im a little plump (200lbs) but he insists im sexy. Im a little too conscious of my weight though that causes me not to dress nice. Is there any way to kick that shyness n take over? Any sites that give tips on kicking shyness? Thank you