The second (and cheaper) path assumes that you have the design and dev chops yourself to build your dream software. Naturally, it’ll take more time to get your product off the ground, but being able to bootstrap the development of your software lets you retain more ownership in your business and be more in control of your path, making this a lower-cost, but higher time investment to make money selling apps.
Etsy: While Etsy's popularity has declined recently, it's still a great resource for selling handmade items online. No need for complex ecommerce sites or merchant accounts or any sort of automation. The company takes a commission of every sale and charges a small listing fee per item. But many still use Etsy as their primary source of income. The best part is that you can also sell digital products on here such as poster designs. 
Create a killer course experience: With your course validated and in the works, you need to figure out how people will take it. Most course creators choose to host their courses (after going down the path of learning how to make a website) on their own blogs. This way, they get all the value of bringing customers back to their site on a regular basis. I host my own courses from a subdomain on my own site so I can easily add more. The course experience is incredibly important as well. And after trying most of the solutions, I highly recommend Teachable—an online platform designed specifically for courses.
Are you just starting your first online business and not sure whether you want to be a product creator or affiliate? Personally, I prefer being an affiliate. It's not as glamorous as owning your own product, but I think it gets much closer to the idea of passive income. Check out how affiliate marketing creates passive income better than any other type of business.
If you're ready to enter the ecommerce fray, you could sell your own stuff. Of course, along with selling your own stuff on your own website comes a whole slew of both responsibilities and technical configuration and requirements. For starters, you'll need a website and a hosting account. You'll also need a merchant account like ones offered by Stripe or PayPal. Then you'll need to design that site, build a sales funnel, create a lead magnet and do some email marketing.
Once you have that problem or need nailed, the next step is to validate that idea and make sure you’ve actually got customers who will pay for it. This means building a minimum viable product, getting objective feedback from real customers, incorporating updates, testing the market for demand, and getting pricing feedback to ensure there’s enough of a margin between your costs and what consumers are willing to pay.
Now, if you don’t know people who might want your coaching services, there are a number of online tools and communities that make it incredibly easy to find clients and teach, on just about any topic area you can think of. Community driven platforms like Savvy.is, Clarity.fm, and Coach.me provide you with a network of potential clients to interact with, as well an integrated payment solution.
I would not bother boosting Facebook posts. That does not perform well. The best strategy is to create a custom audience of your visitors and email list. You may want to use that to create a look-alike audience as well. Then have a sales funnel and email campaign. For instance, you are going to get much better conversion rates from a warm lead who has already received some great free content.
One nice thing about Elegant Themes too is that instead of paying for every theme separately you simply pay one yearly subscription fee and then get unlimited access to all of their different themes. So if you intend to set up several different websites and want some solid themes that are guaranteed to be continually updated and worked on these guys are definitely work a look.
Interest in the niche. Passion/huge interest is a bonus. People really underestimate this point. You’ll be eating, drinking and breathing this product/niche for weeks, possibly months and years to come if it’s successful and you start focusing on growing it. Having an interest in it makes things so much easier and helps you keep going when things get tough.
19. eBay – Of course you can’t read an article about making money online that doesn’t mention eBay. You can start an eBay store and get serious about it or you can just sell some stuff to declutter your home. Either way, I’ve made my fair share from selling on eBay and it’s still a popular way to earn money. If you decide to start an actual eBay store, you’ll want to find a drop-ship business like Doba that will store and ship items straight to your customers so you don’t have to deal with an inventory.

Not only will this multiply the money you’re bringing in in a serious way, but it protects you against any sudden changes in the market or in your business. Remember that old saying about putting all your eggs in one basket? A few hours a week committed to just one or two of the following opportunities will put you in a much stronger position to be financially safe and independent.

If you're serious about making money online, start a blog. Blogging is one of the easiest and most sustainable income sources. As long as the blog is setup the right way, in the right niche, with the right content targeted at the right audience, and the offer is complementary to the content, you could make a tremendous amount of passive income from a blog.

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