During my stay in Kauai, I spent time in both Poipuu beach on the south side of the island, and then one day in Hanalei Bay, on the north. Both were fun, but Hanalei beach was really beautiful, with its majestic cliffs and sandy beach. Renting a surfboard was cheaper in Hanalei too. There is a toothless man with boards in his pickup truck (maybe his name was Amani?), who gave me a board for 2 hours for 10 bucks because it was almost the end of the day. Unfortunately I didn't become an instant surfer, but it was the right setting to aspire to be one.