Set up a pyramid scheme, selling kits that offer to explain to people how to make money by working from home. Recruit agents to sell these kits who pay for the privilege of being agents and get commission for recruiting other agents. Simples.
Seriously, most schemes that someone else invented are either very lowly paid for the time spent or scams in which you pay money for some product/service that you have to sell on.
So you have to initiate an idea yourself.