The key to eliminating the slice from your game is to achieve a more rounded golf swing. This baseball drill will get you swinging around your body on a better swing plane.
Take an old shaft and tee a ball on top of it at about waist height. It takes a bit of practice but by hitting the ball from this position, your arms work around the body in a discuss-like motion.
In turn, your swing will become more rounded and you’ll get a better rotation of the club. By using this drill in your practice, the steep angle of attack that causes the slice will be a distant memory.