Research individual companies in your desired niche: If possible, it’s always better to become an affiliate directly with a company (if they have an internal affiliate program), as no one else will be dipping into your commission rate. This is the preferred route for most of the prominent affiliate marketers, including Pat Flynn. Unfortunately, it’s also the most work, as you’ll have to do the research yourself to see who offers programs (they’re usually listed in the website footer).
Get paid for your opinions. Taking surveys online can be a relatively quick way to earn enough to afford a few extras. Harris Poll Online, for example, awards points for the completion of online surveys, which can take between five and 25 minutes to fill out. Survey takers accumulate points and can redeem them for gift cards from retailers such as Amazon and Starbucks. Other online outfits that will pay you to take surveys include SurveyClub, Global Test Market and Swagbucks. There's no cost to sign up.
Freelancing is working for a company or business but not being part of it. The best reason is you can work on your free time, and work from wherever you want, but there will be deadlines. Usually, the Work or tasks done will Goal oriented. There are online platforms where you can sign up and get projects for SEO, AdWords, Facebook Ads, Copy-writing etc. The Best place to start will be Fiverr, Upwork and Freelancer - Hire & Find Jobs
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.