Ditch the heels- When a woman reaches orgasm- her pelvis arches in a particular way and some heels can cause your pelvis to arch in an unnatural manner lessening orgasm intensity. Flats are your friend.
Drink Water- Sex is exercise after all and you wouldn't do any other sort of exercise without a drink would you? The more you drink the more lubricated your body is.
Avoid the booze- The opposite of water- it dries your body out causing your vagina to dry up or erectile dysfunction.
Wear socks- In a study where men and women were trying to give each other an orgasm- some complained of being cold. When they popped some socks on the achieved more orgasms than those who didn't.
Positive Reinforcement- Women who feel comfortable with the look of their vagina are likely to have more orgasms- so guys- tell her it's the best one you've ever seen!
Mix things up- Women are more likely to achieve orgasm if they engage in different sex acts- so think outside the box when it comes to your sex life.