Don't Overdress
You wouldn't think this would be a problem at a pool party, but it's a good example of people totally out-thinking themselves. Whether it's body issues, dignity, or whatever, some people are still wearing too many clothes to the pool party, and they're paying the price for it in the form of dehydration and sunstroke. Yes, random strangers might think you're slutty, but this is L.A., so just remind yourself that those random strangers have eating disorders, fading career dreams, and daddy issues, and then wear the bathing suit that you're most comfortable in. You might want to avoid straddling the pool railing in the future, but baby steps.