Mana Kai Catamaran pulls up on the shores of Waikiki Beach directly behind the Duke Kahanamoku Statue. Please walk on the beach to board vessel. Check in time 30 minutes prior. Walk to the boat on the shoreline to check in.
You can cancel up to 24 hours in advance of the experience for a full refund.
I think if you want to do this tour, DEFINITELY book for the morning.