Pasai Beach is lined with palm trees which provide some shade and is pleasant for swimming, although at low tide the water is generally around 1 meter high only. There are always a few longtail boats parked (which you can approach for tours of the island or snorkeling excursions).
If you want to enjoy a dominating view, I recommend the Rice Paddy Restaurant, especially for dinner at sunset!
To go visit Pasai Beach, you can also book one of the tours above.