It's called "The Blended Orgasm"
The best way to start is by lying on your back comfortably and letting your body de-stress.When you feel relaxed, begin manually stroking your clitoris lightly. As you become more aroused, increase your presure and speed until you're close to reaching your peak.
Once you're near the brink, take your hand off your clitoris and move in to your G-spot. If you're not sure where your's is, locate it this way: Insert your finger plam-up about an inch or two into your vagina, feeling for a spongy or puckered are along the front wall. You'll know you've found it when a warm, sexy sensation washes over you...one that may even make you feel like you have to pee (b/c your G-spot is near your bladder, it can trigger the urge to urinate, but don't worry it will subside in a few seconds.)
As you massage your G and become increasingly excited, resume stimulating your clitoris with you other hand or a vibrator...but dont take your finger off your G-spot.
I tried it and love it. I suggest doing it while in the shower...you don't have to lay down to attempt!
If it doesn't work for you then you can try jets from a jacuzzi. :]:]