Check your bill to see if a 10% service charge has been added. If it has, you may supplement it by 5% or even more if service was outstanding. If no service charge has been added, then tip as you would at home, about 15%. Be aware that when a large party dines together, a hefty service fee may be added at the end.
The current government tax is 12%, which is mandatory for all diners.
Taxi drivers also expect a tip, about 10% of your fare. Excursion and water-sports staff appreciate tips for their efforts as well; use your discretion.