During what part are you having the crashing problem???

Touch and goes are fairly easy but will test your ability to control the plane during the transition from the touch to the go.

Line up for the takeoff as usual and go. Make your pattern and line up for landing. If all looks good settle down to the ground and a few seconds after touchdown, increase the throttle SLOWLY to take off again at the same time doing everything you normally do for a normal takeoff (rudder correction, etc...). The takeoff will be shorter since you are just below flying speed but otherwise should be just like you took off from a dead stop.

Bouncing off the runway back into the air does not qualify (at least in my eyes) as a touch and go. A touch and go requires a short smooth roll on the ground before liftoff (again, at least in my eyes).