The 69 sex position is a very popular acrobatic position that equals pleasure for both.
But the '68' is a new modification on the standard, but rather than giving pleasure to both partners, it provides immense pleasure to one person - for those selfish moments that we all want.
This position requires one person lying down on their back with their knees bent, and feet flat on the floor. The other partner then lies on top of the 'bottom's' chest with their head on top of their thighs.
If you are a woman, you position your vulva over your partner's mouths, giving them full access to everything they wish to explore, and leaving you to concentrate on how it feels.
As well as being the ultimate in oral sex pleasure, the 68 leaves your hands free to do some exploring and masturbation. If you're on top, it's the perfect opportunity to increase your enjoyment, or if you're on the bottom you get access to every inch of your partner.
It sounds easy, but can be harder than you think: use your elbows to prop you up and take some weight off your partner. Then let the pleasure start.