Our first overlooked opportunity is selling your knowledge. In this instance, we are talking about creating a course or eBook that you can make available for purchasing online. Because of the automation available today, you may be able to put in the work once when creating your packaged information and then enjoy those checks coming in for months or years to come.
Travel blogging is a hard industry to break into. However, the rewards can be worth it, and let’s face it, who doesn’t want to be paid for traveling around the world! There are numerous ways to monetize a travel blog, but affiliate marketing should predominantly be your focus. On your blog, promote hotels, tours, equipment hire services, flights, and anything else travel related. Then take a cut of the proceeds as your audience books their holidays based on your recommendations.
Retain some control. If you upload photos of yourself, or friends/family with consent, it's worth going for the 'rights managed' licence option – otherwise you'll have little to no control over how your images are used (eg, you could star in an ad for haemorrhoid cream). See Alamy's page on understanding stock image licensing for more on the different types of licences.
Before I talk about some of the methods for making money online, I wanted to address the role of pain versus pleasure. Every decision that we make in life is weighed on a pain-versus-pleasure scale. We will always do more to avoid pain than we will to gain pleasure, plain and simple. However, this is also what holds us back from succeeding in any endeavor.
Teaching and tutoring English as a second language is a great way to make money online, not to mention open some doors for you to travel the world if you'd like. While full ESL (English as a Second Language) accreditation is recommended, as long as you’re a native speaker and have the ability to teach, there are people in countries such as Hong Kong or the UAE who are willing to pay upwards of $25/hr for you to tutor them English via Skype. Check out Indeed, Learn4Good and Remote.co for remote english tutoring jobs or sign up on a specialized site like VerbalPlanet or Chegg Tutors. 

Daily Surveys can be taken one or more times per day. This is indicated in the survey description. Other targeted surveys can be taken as you see them. Be sure to complete these when you see them. Some surveys may accept a limited number of responses from people matching your demographics, and can sometimes disappear quickly. New surveys come out all the time too! 

Matched Betting (not available in the USA) enables you to gamble (nearly) risk-free. I say nearly as there is always room for error! It involves placing bets on all outcomes of an event, using free online bets given out by the Bookies. Although it may take a while to get your head around the concept, Matched Betting can make a substantial addition to your monthly income.
Many work-at-home companies hire you as an independent contractor as opposed to an employee. That means you are responsible for submitting your own tax payments. Taxes won't be taken out of your check like you are probably used to. It's so important that you keep good records of your income – and expenses. I highly recommend Quickbooks Self-Employed.
What a huge, great list of ideas – bookmarked this as I know I’ll be coming back to go over it again and again. Here’s another item that could have made the list. I found a financial directory that’s useful for info on making money online. It’s http://money.madbeetech.com. What I like about it is that each directory listing includes ebooks and videos that can be instantly downloaded. All sorts of stuff for people who have their own website, and people who don’t (but still want to make money online).

If you’re a skilled worker in a specific niche, like marketing, design, or software development, there are specialty marketplaces that cater just to you. These are amazing places to make money online as you know that the people visiting them are looking specifically for the skills you have. Check out places like 99Designs or Dribbble for designers, Cloudpeeps for marketing and SEO professionals, and TopTal, Crew, or Gigster for high-level software developers. Once you've built up your development skills, you can begin building a brand for yourself as a higher-value consultant and start charging brands for larger projects like implementing an entire WordPress security overhaul or migrating a website from http to https. 
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