Sex is something everyone claims to be good at, but very few people actually take the time to research it. For a man to be a successful lover, he has to be attentive, fit, and focused. As for a woman, she must be awake-ish and attached to her vagina.
There aren't very many structured ways to learn how to make love. In school, they taught us about sex by showing us pictures of chancres and child birth until crotches were our sworn enemies. And if pornographic movies seem anything remotely close to instruction manuals to you, the girls you're dating have chancres.
Luckily, I searched through dozens of used book stores to find research done on the art of sexing. Say a silent prayer for the genitals of your future lovers, because you're about to read some highly advanced, extremely erotic tips that will take your lovemaking to the next level.