This dress from Urban Outfitters is one of my favorites from the summer. With one or two extra layers, it can easily transition into fall. If your legs need more coverage on cool nights, add gray or black opaque tights, like these reversible ones. The dress would also be great with a thin, double wrap belt - but avoid the urge to use a wide belt, or you may end up looking like Wonder Woman. Not that there's anything wrong with that.