Gumtree or put up flyers at local campuses. My girlfriend did it for a while and enjoyed it. Really good idea to target international students or even workers who are looking to improve their English in order to get permanent visas etc.
Although no-degree jobs isn't exactly the same thing as unskilled... they're not that far off for somebody looking for a good career without a qualification. Many would still need the right experience or for you to work towards them.