If you meet all the participation requirements when the regatta starts, you will see an icon on the right side of your screen. Tap on it to enter the regatta. Members of the Neighborhood complete regatta tasks to get points which add to the total Neighborhood result. Tasks are issued from the regatta interface. Simply select the task you're interested in on the task board and complete it within the specified time. Any items received and goals completed before taking the task don't count.