Start by taking other courses you’re interested in: Not only is this important competitor and opportunity analysis, but it also gives you an idea of how a course could or should look and feel. What’s the pacing like? Is it via email, video, in-person chats? Once you understand how you want your course to look, it’s time to decide what it should include. Those same courses are a great starting place. How can you make your course better or more interesting? Do you have experience others don’t?
Fiverr is one of the biggest providers in the gig economy on the web and you can sell a wide variety of services and products through this medium. Do the research and find out what you can offer. However, keep in mind that like any other money-making task, it takes time to succeed here. And stellar reviews will help you generate more and more income over time.
Multi-vendor marketplaces, like ThemeForest, can be very successful. Chose a niche and create a vendor website for it. Your marketplace could be anything, from a platform for local artists to sell their work on, to an online digital product store. Once set up, invite people in that industry to sell their products on your site. You take a percentage of their profits when items sell.
It’s not the sort of online money making opportunity that’s covered in glory, but everyone needs a set of eyes to make sure the numbers add up at the end of the year. Every business and most individuals need someone to help prepare tax returns, especially time or resource-strapped small business owners. The Income Tax School provides an array of training programs that'll certify you with tax prep in as little as 10 weeks, and once tax season rolls around you'll be able to charge an average of $229 per return as a freelance tax preparer with this side business idea, reports CNBC.
The first widely publicized example of online advertising was conducted via electronic mail. On 3 May 1978, a marketer from DEC (Digital Equipment Corporation), Gary Thuerk, sent an email to most of the ARPANET's American west coast users, advertising an open house for a new model of a DEC computer. Despite the prevailing acceptable use policies, electronic mail marketing rapidly expanded and eventually became known as "spam."
Prior to that group, they had an online community for teachers looking for lesson plans. That probably sounds pretty random, but it's crazy the type of communities you can build and rally people around. If it's something that you're passionate about yourself and you want to connect with others that have that same passion, then an online community is something you should definitely consider.
The difference between Amazon and EBay is that EBay (though still filled with new items) is seen as a used marketplace between individual parties, whereas Amazon (which is filled with offers for new and used merchandise from the 3rd parties) is viewed as a Wal-Mart-type superstore. As a consumer, this difference leads me to use Amazon, so it only makes sense to target on my own demographic.
Find a profitable niche. Starting with your interests, write down as many niche ideas as you can. Think about topics people might search online. Ideas include passions (like surfing or body building), fears (like spiders or speaking in front of crowds) and problems (like getting out of debt). Do keyword research to see it others are interested in the topic. Find out if a domain name is available that matches the keyword 100 percent. 
If you’ve got experience and expertise in a specific area of business, there are hundreds if not thousands of business owners who would love to jump on a phone call and pick your brain. This can be an easy way to make extra money online and to hone your skills to use in your consulting or freelance business. Sites like Clarity.fm let you create a profile where entrepreneurs and business owners can pre-pay to book a phone call with you for a set amount of time. Whether you’re an expert in raising money for startups, building apps, or running a restaurant, you can make extra money selling a few minutes of your time to people in need.