Practice Practice does not make perfect.
Perfect practices make perfect.
Whatever you do in practice, you're going to do in a meet. If you don't work on your start to make it a perfect start, it's not going to be a perfect start. Practice your strokes in front of the mirror at home. It will give you a chance to watch what you're doing and correct any mistakes. Grooving means doing the right thing over and over again until it becomes a habit.