In my experience most people just sit or lie down and get some sun. I find that boring and something I could do at home. I love walking up and down the beach, going in the water, feeling the sun and air on my body and how great it is moving around without the encumbrance of clothes. If I stay still I kinda forget I'm naked. Know what I mean?
sit, swim, go for a walk, play frisbee or football or cornhole or this weird game we play around here involving rolling softballs into holes in the sand, kayak, paddleboard, boat, tube, go out on the breakwall, jump off the lighthouse, have a fire, drink beer (in conjunction with most of the previously named activities). of course, that's when i'm not working. at work there's lifeguarding, training lifeguards, teaching kayaking/paddleboarding/boating, running special events, networking, etc.
Took a week off in 2007 and spent it at Orlando Beach...worst vacation I ever took; I was bored after 10 minutes. I should have gone out west to the mountains.
Stretching out in the sun, walks along the drift line, reading, playing frisbee, playing volleyball, reading books, chatting, watching the sunset (iedally with a bottle of red wine coming along with some tapas and someone to lean on), reading books, cuddling, building sand castles, swimming, snorkling, dabbling, reading books ... probably half of the amount of books i've ever read i did read at the beach ;-)
I like to go barefoot and dip my toes in the water and just stare out to sea thinking 'God, I'm actually here.' Have an ice cream and skim stones.
Strip, dance to Occidentali's Karma, then grab the body board and run, run, run! Often the beach is too blazing hot in the Australian summer. So evening is better, but then I have a hard time finding the water in the dark!!