I don't know of any specific good way to level up sailing, but I would say just sail as often as you can and go after some higher level ships. Get some fellow guild members together, or even some friends, crew up, and plunder, using your broadsides as much as you can. Rinse and repeat. I'm 3 levels away from mastered sailing, and lvl 33 notoriety, but I sail a lot, even if I have no one to sail with. I love to sail though so that helps me. I know some don't like to sail. Anyway, fair winds Tab.
