WHAT TO BRING
Walking around on hot pavement is tough on feet, so buy a cheap pair of water slippers that you can leave on (although a few parks, like Disney's, don't allow them on body slides)
Some parks, like Noah's Ark, have mailbox-like slots for flip-flops at the entrance to each ride's queue, but most parks only provide lockers, and you must pay for each use
Waterproof sunscreen is a must because while you're in line, you'll be exposed to the sun
WHAT TO WEAR
Newfangled body slides will have you zipping at up to 60 mph, so minimize clothing loss by wearing loose trunks (guys) and one-piece suits (girls)
Suits with zippers and buttons scratch flumes, so many parks have banned them
Some suits now come with built-in waterproof plastic pouches that you can use to seal your money (but don't put keys in there unless you want to bruise yourself)
Use plastic swim diapers for toddlers
ADVANCE CONSIDERATIONS
The scariest rides have height minimums; 42" is common
Every water slide park has a dedicated kiddie area
Everyone gets the same idea on summer's hottest days, so on those busy days, arrive at opening to stake out a chair
If there are thunderstorms in the forecast, delay your visit, because slides shut down at the hint of lightning
Eat your Wheaties, because most rides require you to climb stairs to the top
Note: This story was accurate when it was published. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.