You're already mostly naked. Follow this guide so you won't make a gaffe that'll expose you even more.
Do: Throw the pigskin around.
Don't: Run jerky patterns like you used to start at wide receiver when everybody knows you were a backup equipment manager.
Do: Bring something to read.
Don't: Bring a financial periodical. If you were so important you couldn't miss a few hours of news, you'd probably own this beach.
Do: Help a lady apply sunscreen.
Don't: Assume her asking for help means she wants to bear you a son.
Do: Write inappropriate phrases on sleeping friends with the aforementioned sunscreen.
Don’t: Misspell the inappropriate phrases. Illiteracy is far more embarrassing than [insert inappropriate phrase here].
Do: Wear a mankini.
Don’t: Believe everything you read.
That's enough for now. Now throw on your knee-length board shorts and go have some fun.