These pay-per-click ads appear on your blog. Every time somebody clicks on an ad (which is supposed to be about a subject related to your niche), you make a few cents or more. Small amounts each time, but it adds up. This is extremely hands-off. You just need to get a code from Google, place it on your website - and the ads will automatically appear on your blog. Google will only show ads that are relevant to your blog so it's a good experience for your visitors and maximizes the number of clicks you get, meaning more income.
Yes, it costs money, but starting any business takes an investment. The key is to invest wisely, be frugal, and make sure you’re investing in the right things. With Wealthy Affiliate Premium you are literally getting absolutely everything you’ll need to start a successful business online. From the training to the web building tools to the website hosting, backup, security, and support – it’s all there in one place at a very reasonable price.
There's an audience for everything, even if it's as specific as dollhouse furniture or organic dog food. With a niche e-commerce store, you can reach customers who seek your specific products. Building a business in a niche market can help you differentiate yourself from other brands and build your credibility and expertise. Look to social media or your own consumer needs to come up with a product to sell online.  
Unfortunately, I am not acquainted with Indian Tax law, so I am not able to advice you on this. But, I would presume that if you earn income from affiliate marketing, your profit from the business will be tax under your personal income. That is unless you create a company to run the operation, then it will be subject to corporate tax, and the dividends receive from the company will be subject to your local personal tax.

To get your e-commerce business up and running, all you need is a web hosting service with an integrated shopping cart feature or e-commerce software. To simplify the shipping process, you can work with vendors to ship products to customers on your behalf. This can reduce the amount of inventory you need to keep onsite. [Related: A Small Business Guide to E-Commerce Shipping]

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