Girls, the best and most proven masturbation technique is to completely undress and get into an empty bath with warm water running out the tap. Depending on whether the taps are at the far end or on...
use a chair leg. tilt it a bit so that it goes all the way. i love the sitting position for the girl where the penis it pointing straight up. try that one on the chair.
rubbing by your fingers...
The same as for men according to recent studies. Tingeling, itchy and you can't really stop when you reach a certain level. It's incredibly hard to put words on.