Becoming a VA can entail some degree of training or briefing, depending on your qualifications. However, if you have good communication skills and are capable of using applications like MS Office, you can just sign up on sites such as Elance.com, 24/7 Virtual Assistant, Assistant Match, eaHelp, Freelancer, FlexJobs, People Per Hour, Uassist.Me, Upwork, VaVa Virtual Assistants, Virtual Staff Finder, Worldwide 101, Ziptask, Zirtual and so on. A VA my expect earnings in the range of Rs 500-Rs 4,000 per hour.
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.