Lucky you!!!! I hope you have a WONDERFUL trip. I am a cliff lover so I will give you my two cents......

With only one night on the cliffs - just snorkel or stare at the sea and soak up the sun when you get there (cold Red Stripe maybe?) - shower, have a nice dinner onsite or walk or taxi to one of many delicious choices (De Bar jerk chicken; Chicken Lavish; Choices; Canoe). Then the MUST DO is to (have some rum maybe?) watch the sunset - then converstation and maybe dominos (if you prefer music/drinking try out No Limit Bar, Sea View, De Bar, Mi Yard). My favorite part of staying on the cliffs is just "being" there by the sea - doesn't get much better than that feeling and I don't want to be anywhere else.