Well not exactly. With proper planning some income streams will almost take care of themselves. For instance consider investments in stocks or bonds, they don't need lots of work to deal with. In fact the less work you do with those after your initial purchase the better as leaving them alone is more cost effective,
Spread your time evenly over those income streams that require you deal with matters regularly. So blog often on successful traffic generating blogs. Take care of Search Engine Optimization (SEO), update your skills as required, it is surprising how skills quickly dull as you don't use them.
Keepp a diary for ideas. It may just be a notebook. As ideas come to you for products, services, blog posts or such, write them down in outline straight away. Most ideas you can forget, but your notes will allow you to remember the real gems.
Check your idea diary regularlyfor ideas. The more ideas that you note down the more ideas you will get. It is surprising how once started the flow of ideas comes more easily.
Accept time as a real cost. It can take several months for an idea to bear fruit with a small cash stream. Keep working the paying streams and only let them go if they don't show a real return after two years at least.