Find work. When you first start out, you may have to accept work writing about a topic you don’t find all that interesting. You must keep an open mind and be willing to accept work that may not be in your desired field. However, as you continue to write, you not only learn about more topics, but you also build your reputation. With time, you can be choosier about assignments you want to accept.
Rather than making money through subscriptions, YouTube channels are based on a traditional advertising system. Meaning the more viewers you get, the more you make. Once you’re approved for the YouTube Partner Program and can start including ads on your videos, with every 1,000 views, you will make approximately $2-$4. Which might not seem like a lot, but if you have 100 videos with 5,000 views a month each, that would be $1,000–$2,000 already. Just imagine if your videos start hitting millions of views!
There are many ways to get people onto your list. Lead magnets are one such resource. For example, you can build ebooks, checklists and cheat sheets. But you can also do content upgrades, such as PDF versions of an article with added resources in them, four-part video training series, and more. Think about your audience and what you can offer them to better serve them, then treat them with some respect and you'll eventually reap the rewards.
The best smartphone apps are based on the freemium model, which allows some level of game play or usage without having to purchase. But this also means that you have to build something with real inherent value. It also has to be highly engaging if people are even going to consider paying for an in-app purchase. Take the time to really research this money making opportunity before diving in head first.
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.
One of the cool things about Google AdSense is that it's so easy to get set up. If you have a blog or website, you can sign up for a free Google AdSense Account. From there, Google will give you a unique code that you will paste onto your website. Google takes it from there, tracking your page views, traffic, and earnings on your behalf. There is no upkeep or maintenance to get this thing going, which makes it a no-brainer if you have a website already.