What sort of material is it? Canvas, nylon? There are several repair kits on the towsure site, including two different marine ones which should make a good repair. If you need to repair it soonish, put some duck tape over the hole until you get the proper stuff.
If its a lightweight awning like tent material, Tenacious tape is brilliant . I used it to repair a hole in a synthetic tent roof 2 years ago , still watertight , almost invisible repair as its clear tape.