If you have a background in a specific field, you may find there is a demand for writing industry papers in your area of expertise. For example, there are often adverts for doctors, lawyers, nutritionists, and business experts from particular niches, to write white papers on different subject areas. These are well paid jobs that you will need to stake your reputation on, but that can often be worked on from the comfort of your own home.
Now, this isn't about some get-rich-quick method here. If you want to get rich quick, forget about trying to do it on the internet. Sure, Facebook ads are all the craze, but without a serious understanding of the mechanics behind sales funnels and conversion optimizations, which only comes after years and years of in-the-trenches work in the internet marketing field, you're largely wasting your time trying to "get rich quick."
Last but not least, you can also earn money online by building an online community, although the monetization strategies you can pursue will vary a lot depending on your goals. You can build a community with a blog, for example. You can also build an online forum and charge people for membership. You could even build up a Facebook group and use your influence there to sell and promote products.
High-ticket consulting or coaching: You could sell your own high-ticket consulting or coaching products from your website. You'll still need a website, merchant account, sales funnel, lead magnet and many other items. But you can easily earn a substantial amount of money from each individual customer, making it well worth the arduous setup required. 
For those with a large Twitter following, you can make money from your Tweets alone with Sponsored Tweets. You could be paid for sharing a business’s information, recommending restaurants or hotels, or tweeting pictures of you using or wearing products. As with all sponsored posts on social media, businesses will only be prepared to pay you to Tweet if you have a large following that you can influence. So work hard on building up a loyal fan base.
Whether you have a website or are still dreaming up ideas for a blog, you can also look into affiliate marketing. With affiliate marketing, you partner with brands and businesses within the content of your website. If you mention a product or service, you link to that produce or service using a unique affiliate code you received when you signed up for that particular affiliate program. From there, you’ll make money any time someone buys a product or service through your link.
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