There are a few laundry facilities around town..you leave your clothes at the laundry facility and they charge by the pound to wash, dry and fold.
One location is in the West End at the beginning of Tigress Lane near Miyard...another in the West End past the Lighthouse, located on Hylton Ave...and another located near the bus park, just past the police station.

The easiest option is to ask your hotel housekeeper if they'll do laundry or know of someone that will...they'll often do this for you as will many people around town.