The easiest way to make truly passive income is to invest your money into a stock, ETF, mutual funds, etc. The richest people tend to get even richer because they consistently invest and reinvest their money. Keep it up, and you might even be able to never have to work again. I know one guy whose investments now earn roughly $50,000 a year in dividends, and so he is free to live without working if he so chooses.
Peer-to-Peer Lending: Earn up to 10% in returns by lending individuals, organizations and small companies who don't qualify for traditional financing through peer-to-peer lending platforms like Lending Club. You can lend $100, $1,000, or more to borrowers who meet lending platform financial standards. Like a bank, you'll earn interest on the loan - often at higher returns than banks usually get.

I also noticed that in your passive income chart at the bottom that you don’t include your internet income other than sales from your book. Is there a reason for that? Do you not consider is passive because you are actively blogging all the time to create it? Or do you just not want readers to know how much money you generate from blogging activities?
Investing in rental properties is an effective way to earn passive income. But it often requires more work than people expect. If you don’t take the time to learn how to make it a profitable venture, you could lose your investment and then some, says John H. Graves, an Accredited Investment Fiduciary (AIF) in the Los Angeles area and author of “The 7% Solution: You Can Afford a Comfortable Retirement.”
But that’s more like a fairytale. You’ll have to put in some effort to continue receiving residual income on the business you started. Talking to your managers and representatives will help them be more productive and run your business better. Marketing your online sales through social media and your network will help earn you more money. But you just won’t have to work at it as your full time job. Think of it as a part time job that can potentially bring in full time pay.
Many people talk about passive income and create the impression that you never have to do anything to keep that income going. The truth is that you will normally have to keep your eye on things if you want it to run smoothly. For example Richard Branson doesn’t run any of the 400+ companies he started but he goes over the numbers each day to make sure they’re performing well and calls the CEO if there are any problems.