A few of suggestions:
1) Use a Continental grip or an Eastern BH grip. (You will probably get more spin using an Eastern BH as it presents a more closed racket face to the ball at impact.)
2) To get the most pure slice (side) spin, place your toss farther to the right (if you are right handed). If you want to hit more of a topspin slice (combined topspin and slice spins), place your toss the ball farther to the left (but not as far left as you would for a kick or twist serve.)
3) If you want more pace on your serve, toss the ball into the court more and get your weight moving forward at impact.
4) Hitting an accurate/consistent can opener takes a lot of practice and timing. A topspin slice is much easier to place consistently IMHO. It has a higher net clearance and more margin for error.
5) There are lots of instructional videos online, just search for slice serve or topspin slice serve.
Last edited by Fearsome Forehand; 03-13-2013 at 07:27 AM.