First things first. Eating lunch at the "Salty Dog "restaurant at the marina on South Beach Sea Pines. Salty Dog is the quintessential touristy place to eat and it's a great spot overlooking the marina. I love their shrimp salad plate. Next is shopping (or window shopping) on South Beach. Great shops and not so many that it's overwhelming. Next, sit in one of the many rockers or benches and enjoy the sun, people, and boat watching. IMPORTANT, only go to Hilton Head in February. Spring summer and fall are insanely crowded.
If you read "The Curious Incident of the Dog in the Night Time " and loved it as I did be sure to attend the theater show if it's around your area. The play is an unusual production, very engrossing, and beautifully presented. Highly recommend. I saw it at the Theater next to the Art Center of Coastal Carolina, in Shelter Cove. A wonderful theater that is also on my highly recommended list.
I was very lucky to be on Hilton Head while the "Gullah Celebration" was in progress. I went to the Art Center, next door to the theater, and caught the Opening of the Gullah Art Show. It was a fantastic event and the art is so joyful and colorful. One of the artists I particularly liked was Amiri Farris. look him up on the internet.