In the “Viennese Oyster” position the woman lays on her back with her lower back and legs raised all the way up by bending at the waist so that their ankles are crossed behind their own head. The exact end position will depend on the flexibility of the woman and her comfort level. This position exposes the pelvis to the man who lays atop the woman to thrust in to her. The man moves in a way that creates friction on the woman, which gives her clitoral stimulation as well as vaginal. The man should use his hands to support his weight so as not to crush the woman underneath him.
This position requires considerable flexibility on the part of woman, but the total exposure of the position creates a sort of kinkiness that will drive her wild. Couples that are less flexible should still attempt this position, but always stop at the point where the position starts to become uncomfortable so as to not exert yourselves too much.