Alright: I am not G-Spot expert and this threat has been directed to ladies but i got my own style to let u know how to find it.
Ladies tell your man to do the following instruction..
as for the start he have to do some oral stimulation to turn u on and wet to make u relax first.
1: tell your man to put 2 fingers on your vagina. The 2 fingers are ring finger also the middle finger (long one).
2: (this is an option but very important) Tell your man to create an angle.. The angle should be created with a little finger touching your asshole. Note: There is a lot of feeling on your anal area so tell him to stimulate that with little finger or to go in out as much as he can. ( vagina fingers also the little one in ass should be moved on same time to create double feeling). Now when he placed hes little finger on your ass as the same time fingers on your vagina (Finally he created the right angle for G-Spot Simulation.
3: when he go with come here motion inside your vagina also stimulation your ass ---- tell him in same time to place his left hand (palm) 2 or 2.5 inches above clitoris and tell him to press that area down (gentle) with rub motion (So pressure down with a rub motion).
4: all 3 techniques above has to be done in same time (to much for a man ? don`t think so)
5: Ladies.. this is your part: Now as your man do all this 3 motions in same time - u have to do kegels every 10 or 15 seconds in same time - to build up your G-spot and making the area bigger.
6: Put your stopwatch and cound to 2 min Max (Max 2 min) and u will orgasm like never before in your life)
Let me know if u try this 