The old saying "You are only as good as your second serve" is still true. Many players can crack a first serve, but in crunch time you will need to rely on your second serve. Obviously there might be some technical flaws that need to be fixed, but in general it is recommended to move the grip over towards the backhand grip to increase safety.

Once you do that the serves might go into the net in the beginning. It is recommended to serve from well inside the court until you get the feel and gradually move back until you are ready to serve from the baseline. It is important to snap the wrist up and to the right (or to the left if you are left handed) and to accelerate as you connect. Another source of power can be a deep bending of the knees just before the contact.

You should always serve with targets and a high net, and also practice serving and volleying with only one serve--this will help create more body weight shift into the shot.