Each lesson, follow the Open House Cheat Sheet so you and the kids know the order (tape the laminated one found in the bottom of the pencil case box, to the side of the pool and take picture for me so we are on same page and don't forget to return the laminated cheat sheet to the pencil case box at the end of your shift).
Make sure you know what you are going to tell parents about how the kids have improved ("based on my professional eye"). It is important that you show your worth and the programs worth to the parents so they see the lessons as a worthwhile investment and so they see our lessons and our coaches are far superior then the municipal lessons (which are often cheaper).
Don't forget to time the warm-up so you know how many lengths the kids can get done in that amount of time, also tweak/update/change lesson plans accordingly. Practice introducing each skill to an imaginary audience as you do your dress rehearsals.