Take with you: parcel string, camera (if you want something nice for your collection), waterproof dildo and plug (if available) and a swimsuit.
If you do not have a suitable mobile device you can print out your instructions (http://ul.to/jlr308). If you do not have a printer you can read it now and memorize it, but this would ruin part of the fun.
If your local swimming bath/pool has no single dressing rooms it might be a good idea to read the initial instructions now ;)
If you are ready go to the swimming bath. See you later.