How to look slim in swimsuit, please help?

i;m 16, male. I gotta party in one week, and the guy has a hottub. i have a belly, that's it, and it looks pretty awful, not that bad, but sticks out. i'll wear swimming shorts. not going in the hottub is not really an option, it looks weird, or unless u can give me a believable excuse. i'm goin to this party, and there's hot girls there. i have slim face and everything, except my belly. how do i fake being slim, and hide my gut from other people, so they think i;m not fat? i'm tempted to starve my slef, would that help?