If you have a pool, a beach party theme is a natural. Throw a few beach balls around and encourage folks to dress in their swimsuits or short shorts for the occasion. Decorate your table with brightly colored terrycloth towels instead of a conventional tablecloth, and opt for some nifty beach-classic graphic elements, like polka dots or bold stripes. Play to the crowd with 60s-era music or something more modern, and keep it lively. Offer finger food that's portable and has picnic nostalgia, like fried chicken or hot dogs. Early evening is the perfect time to light up your fire pit if you have one and roast some marshmallows in front of your own faux beachfront bonfire.