If Barbara Keesling, Ph.D., could give just one piece of advice to men and to women, this sex therapist would say the following: "Sex is about enjoying yourself, not putting on a show. Guys, get over the performance thing. And ladies, don't expect your partner to know how to touch your body and how to find its hot spots until you know how yourself." Simple erotic wisdom is Keesling's hallmark in a trade she has plied for more than a decade. At 39, she has worked as a sex surrogate, earned a doctorate in psychology, written three books on lovemaking and launched a sex therapy practice. Keesling now includes Playboy on her very sexy résumé. "When I wrote my latest book," she says, "I hoped it might get me into Playboy. Looks like I was right." Her first two sex guides could be considered bedside primers. Sexual Healing, published in 1990, deals with treating sexual dysfunctions, and 1993's Sexual Pleasure explores the female libido and sensuality for couples. Her latest manual, How to Make Love All Night (and Drive a Woman Wild), unlocks the secrets of prolonged sex, notably a man's ability to achieve what was once considered an exclusively female treasure: multiple orgasms. Already in its second printing, the book is only the latest chapter in Barbara's study of the joys of the flesh. "There's always something new to learn about sex," she says, "and always something new that feels good." Born in Pasadena, Barbara attended Catholic high school in Torrance, California, then headed straight into the job market. "I did six years with the Postal Service," she says, "but spent most of my time there thinking of ways to get out." In 1980 she found one. While taking a course on human sexuality, Barbara learned about the sex surrogate business, and before you could say, "What's up, Doc?" she was getting naked with five clients a week. "I treated men by using touching exercises and hands-on counseling. And, no, I never found a client I was tempted to keep--though I must say they all came out pretty well." Fifteen years and three degrees later, Barbara now operates a counseling-only practice in California--that is, when she's not doing book tours and talk shows. With such a packed schedule, does she have any time left to meet men and practice what she preaches? "Not lately," Barbara admits, then smiles. "But I am hoping to remedy that situation."