I think Voodooo doll has some good ideas, but I know I'd never ever ever never ever go around the block in cosplay. Cosplay goes from house to car to event, and that's it for me. Maybe a drive-through or something, but that's it until I get to the convention. Being alone in costume is far more nerve wracking than being among fellow cosplayers.
Smaller conventions and photoshoots are the best way to go.