Great way to start making a passive income is to create an online blog.
A blog is a dynamic website that gets updated with new content as often as you like. Its referred to as a post or "posting".
I recommend posting at least once every day. Once the blog has some good traffic you can slower your posting rate.

Now you ask how does a blog make money?
There is more than 1 way of making money from a blog.

Advertising

You can place banners or Text ads on your blog that will generate revenue for you.

Paid Post

Companies often pay bloggers to post reviews on their products.

Other revenue streams

This is were your own creativity can make up other ways of generating money from your blog. For example you can sell products from your blog.

Types of blogs you can start:
Visit this blog post to check out some types of blogs you get: 20 Types of blogs

Some types are easier to make money from them than others.
What I recommend is targeting a niche(specific) market. Choose something that you know allot about, it might be Gardening, or 3d modeling.
Don't make your blog a general blog about lots of different topics.
Targeting a niche market will make your blog the main source for information on that topic. Google will see your website as a great resource on that topic and rank your blog very well on related keywords.

How do I start a blog?
There are a number of websites that give you the tools to start a blog for free. You don't need to know any coding.
Here are some websites you may use to start a free blog:
Blogspot.com

It's a very good advice to have an online blog so that you can have extra money coming.so,johny where to get advertisers?I do have a blog and an online business but so far no money is coming in.

Hi Real

Excellent to hear that you have a blog. For me to give you advice on how you could make some money from it could you please give me your blog link?

I can also have a look at your online business.

I look forward to your reply..

check it on http://www.changinglife.iblog.co.za

thanks.