If you are an all-around hard worker…
Sell vouchers (or books of vouchers) entitling the buyer to an hour (or more) of work. You may want to design two types of vouchers – one with a higher purchase price for more strenuous work that would take more than one hour, and another with a lower price for easier work or work that would take less than one hour. List the type of work that you are willing/able to do on the voucher. Advertise your voucher around your school, church, or community. When you have sold a voucher (or book of vouchers), set up a time when the buyer would like you to come and do the work. If the buyer bought only one voucher for one hour of work, offer to sell them another voucher when you finish your hour. They may be interested if you prove to be a good worker.