If you have been using them, STOP NOW!
Your child will observe you and pick up on your feelings. If you appear relaxed and content your child's progress will be enhanced.
Leading up to and during the lessons, too much parental discussion or reaction will only produce anxiety. Keep comments short, matter-of-fact, and positive. Do not acknowledge negative comments or behavior. For example, do not tell your child not to cry at any point before during or after the swim lessons. When you do acknowledge adverse behavior, you will prolong that behavior.