1. Open Up
For his book The Art of Kissing, William Cane asked men what their biggest complaints and desires were regarding kissing. The results? Stop holding back, ladies! According to the research, the number one mistake women make is not opening their mouths wide enough. Dr. Helen Fisher, a professor of biological anthropology at Rutgers University in New Jersey, theorizes this is because the sloppier the smooch, the more saliva—and hence, hormonal information—is exchanged. Fisher suggests that men may use this hormonal input to subconsciously gauge their partner’s fertility and reproductive potential.

Also Enjoy: Why You Need to Read the Kama Sutra