Chill out like a motherfucker, stick on some Cypress Hill and other trippy songs....Yesterday while sitting in a random tent I just lay there with my girlfriend, everybody else chilled out to.....goooood shit.
Make shadow puppets....that is hilarious for me...
Play with a pet....you seem to be able to understand them more when you are high. Normally my dog is hyper but when we smoke weed he knows just to chill out. Goldfish are the best thing ever to watch when your high....I love 'em!
Play a really scary video game....Ive been playing area 51 on the playstation 2 a lot when stoned with my friends and although the storyline is confusing even to sober people the actual game is amazing.