Well, that's not a bad way to go about it. Let's see, where to start...
Ah, yes-- first, your dominant hand should grip the gun high on the back strap— that way you'll have more leverage against it, and that helps controlling the recoil when you fire. Your other hand should be pressed firmly against the exposed portion of the grip not covered by your dominant hand. All the four fingers of your support hand need to be under the trigger guard, with the index finger pressed hard underneath it.
That's how to hold it, pretty much. Then you need to work on your shooting position.