If you’re a fitness buff and have the right combination of charisma and business sense, working as a part-time online personal trainer can be both physically and financially rewarding. Once you build up a reputation and client base for yourself, it could easily turn into a full-time endeavor for you. Check out this interview with several fitness blog owners who are making a living online, from MonetizePros. As well, I'd recommend checking out this resource if you want to take this business idea seriously and get started with a business plan for your personal fitness trainer business today.
Drive for Uber or Lyft: If you're in a locale where you can find Uber or Lyft (or even one of the many competitors around the world such as China's Didi), you could easily make a respectable income. The hours are flexible and you can work as you see fit, making it perfect even if you currently have full-time employment but are looking to make some money on the side. 
You could also opt to use existing websites for making money. These include both active income and passive income methods. For example, you could sell some used items or invest in creating some digital designs that then can be sold on merchandise. Again, devote a sizable portion of your time to passive income so that you can slowly build up earnings that will arrive on autopilot without any extra added effort. 
Money can be earned and spent, saved and pilfered, invested and wasted. Not time. That's why time is far more valuable than money. The point? When you lack the luxury of time, making money online (or offline) can seem like an impossible task. How are you supposed to do that when you're working at a life-sucking nine-to-five job? While the stability of full-time employment might allow most to sleep well at night, it doesn't empower your creative juices to search for new income-producing strategies.

Amazon will have you work on micro-projects that require some sort of human interaction. Tasks can include translating a paragraph into English (or another language), rating the search results for certain keywords, or reworking an article. The tasks are simple, and you will be paid a small amount to complete each. But if you do enough tasks quickly, you can make a respectable amount of money.
Mechanical Turk is Amazon's take on micro-jobs. These are small miniscule-jobs that you can do for other people, which they call HITs, or Human Intelligence Tasks. These are super simple tasks that anyone can do. Some examples are listing off some URLs with certain kinds of images for one cent, or recording a few phrases with a microphone for 6 cents.
Once you have decided what type of product you are going to sell, you need to decide where to sell them. Selling merchandise on Amazon or eBay aren’t your only options. Creating your own eCommerce store is another way to promote your products and generate sales. Once you have decided what you are going to sell, whether it is white labeled products, your own designs, or other people’s merchandise, you can set up an eCommerce website to display these products.
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.

When creating a membership site, always offer different plans and pricing tiers to appeal to your different categories of audience. Access to specific types of content is then dependent on the plan selected by a member. Membership fees can be a one-off payment or a repeat subscription. And you can even sell products on your membership site to boost your income.
Now, I know what you’re thinking. Most of the software and apps you use on a regular basis are made by massive companies or established development studios. Well, yes. But many successful apps, particularly those in the Apple and Google stores, are created and marketed by individuals and small businesses. In fact, independent developers made $20 billion in the App Store in 2016 alone.
There are quite literally hundreds of clever ways to make money online. From taking online surveys, to renting or selling your old clothes, flipping your iPhone to someone in a different country, and even buying low-cost products locally, just to resell them for a higher price on Amazon. There’s truly no shortage of unique ways to make money online.
Market your course: The beauty of using a course to make money online is that you can continue to sell it for as long as you’d like. Look for niche communities on Facebook, LinkedIn, or Reddit that might benefit from your content. Guest post on relevant blogs and sites. Look for anywhere you might be able to get in front of the right people. With just a few hours a month you can continue to generate sales.
Next, you’ll need the right tools. You can be as complicated or simple as you want depending on your comfort with audio equipment, but at the minimum you’ll want a microphone and software for recording your voice. Companies like Behringer, Blue, Focusrite, and others sell studio-quality plug-and-play podcast setups that can get you recording today.

Holly told me she started writing content in 2011. At the time, she still worked a full-time job but created content online part-time to supplement her income. Over time, she was able to double and triple her rates until she could quit her full-time job to write. These days, she makes bank as a freelance writer and teaches others to do the same via her online course, Earn More Writing.
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