the best possible thing you can do is find someone who can teach you. its really simple but its better to see someone do it in person. and dont be too afraid of making mistakes cause you can always pull out the screw and do it over again.
so what you want to do is hold the screw in place with your left (assuming your right handed) and put the tip of the drill in the notches of the screw. hold the drill firmly and directly over the screw. being straight down on it is very important. then simply ease on the trigger and slowly start the screw in. once the screw can stand by itself you can let go of it and pull the trigger farther until the screw is down far enough.
always remember to press firmly down on the screw or the bit will jump and scrape up the screw and your bit.