To add more income, you can also join GPT sites where you can earn money by taking small surveys,
watching videos, playing games & doing many more activities.If you have more time then you can add
further income in your pocket by working as a captcha solver. This is the one of easiest way to earn
money online.Although this one is the most favourite in my list but I put this in #4 because its not as
easy as other 3 above & it takes time to make money from Google AdSense.
about survey in my experience this is just waste of time but maybe you have then like 20-30 a day so you can make money.
Honestly this is the worst way one survey to all register user and only several are able to do it