How do I loose weight with out that much exercise?

Um, im 17 and 5"6' and i weigh 179. im not that pudgy, but im going to Mexico and california for spring break in a few months and i wanna loose 30 pounds before then. I dont get home until 8 every night, and i snowboard 6 hours every saturday and sunday, and 3 hours every friday. any tips please? (No gross answers, just legit ones please)