1) Talk dirty
According to a UCLA study, women who are unhappy with their breast size are 16 times more likely to hide their breasts during sex. Which is a bummer, because you don't just want to see her breasts — you also want her to feel safe and secure and turned-on.
It might help to compliment her on her breasts early in foreplay. “Comment on her high responsiveness to stimulation,” says Patti Britton, Ph.D., a clinical sexologist (i.e., "your nipples are so hard right now.") Alternatively, something as simple as "Oh, wow, you have amazing boobs" could be just the confidence boost she needs.
2) Don't head for the nipple right away
As Debby Herbenick, PhD, previously explained to MensHealth.com, nipples vary widely in terms of sensitivity, so if you're not quite sure what she likes, you need to work your way up to nipple stimulation. Start off by gently stroking or massaging the tops, bottoms, and sides of her breasts. Alternate with lightly kissing her neck, earlobes, and collarbone. That'll help build anticipation and leave her wanting more.
3) Focus on the areola
When you feel like she's ready — and if she's making a lot of noise or writhing around with pleasure, she's probably ready — move onto the areola, the dark-colored circle that surrounds the nipple, which is actually more sensitive than the nipple itself. Focus especially on the upper quadrant of her breast, between 10 and 2 o’clock. It’s the most sensitive part of the bull’s-eye. Gently stroke the nipple and circle the areola with a finger, or circle the nipple with your thumb and forefinger.
4) Get your mouth involved — but be gentle
If she seems to be enjoying herself, use your tongue to very lightly draw circles around her nipple. If her nipple is erect, gently flick it with your tongue a few times before slowly and gently taking her nipple into your mouth. Alternate between licking and sucking on her nipple. (If she has inverted nipples, which approximately 10 to 20 per cent of women do, you can lure the nipples out with touching, kissing, licking, and gentle sucking, but you might have to work a little harder.)
After a while, you can give your mouth a break and go back to gently circling and stroking her nipples — she might enjoy the varying pressure.
5) Don't bite — unless she asks you to
Even if she's writhing and moaning with pleasure, you shouldn't get carried away and bite or pull her nipple without her consent. If you sense that she might like it rough, ask, "Do you want more?" or "Harder?" before nibbling on or pulling on her nipple. While some women really enjoy rough breast play, others do not, and you don't want to interrupt your good time or hers by crossing that line without her consent.
6) Do not bounce, jiggle, honk, or slap
While some women may very well be into having their boobs honked during sex, they are likely few and far between. Because so much of breast sensitivity is concentrated in the nipple, groping or jiggling will do literally nothing for most women. (This is also why putting your penis in between her breasts, while it may look cool and be fun for you, is probably not your partner's favorite activity.) When it comes to breast play, it's usually best to be gentle and work your way up if it seems like she wants it rougher. "Slow and steady wins the race" is a good rule of thumb.
7) Different types of breasts enjoy different things
In a study conducted at the University of Vienna, researchers found that large breasts were about 24% less sensitive than small ones. “This is probably because the nerve that transmits sensation from the nipple is stretched,” says Dr. Alan Matarasso, a plastic surgeon in New York City. So if your partner has larger breasts, you may want to spend more time stimulating the outer sides of her breasts, just below the armpits, with your tongue or fingertips.
Similarly, if she's pregnant, nursing, or on her period, her nipples will be tender. (And this is assuming that she wants you to play with her breasts at all — many women do not, particularly if they're breastfeeding.) Focus on her underboob, which is a frequently neglected area, and gently cup and support her breasts.