Question about Spa World - Centreville, VA

I am planning my first visit to Spa World in Centreville, VA and would like advice on how to plan the visit. I bought a Groupon that includes admission and a 30-minute shiatsu massage. A friend and I will drive up from Richmond (so not arrive until at least late morning), spend the day (probably including lunch), and then go into DC to check into a hotel, get cleaned up, have dinner and go out to party. In what order should I plan to partake in the massage and other amenities (pools, poulstice rooms, etc)?

Thanks in advance!!!