vaginal weight lifting.
kegel exercise (google for more specific instructions): basically you clench your vaginal muscles, hold for a few seconds, and release (put a finger or two in to check if you're feeling it and doing it right).
There are "weights" to help with the exercises (they are called vaginal cones)
a very good exercise for exercise instructions and types:
http://www.whitelotuseast.com/YoniExercises.htm
