Many slices are caused by a poor backswing. You take the club back too far inside the target line, which prompts you to re-route it to the outside on the downswing, and you cut across the ball with an open clubface. To avoid getting the club into a bad backswing position, think Drag it back.
That’s if you feel like you control the takeaway with your right hand. Think Push it back if you feel more left-hand oriented at the start of the swing. Either way, this cue will improve your swing path and set your 3-to-1 tempo. Just remember to think Finish as you swing down.