How To Create Your Own Product Or Niche

After You Create Your Product have others sell for you.
How To Create an Affiliate Site
Choose a product – it should be something you have used and are familiar with.
Sign up for the affiliate product through the official product website.
Write an article explaining the benefits of the product. Be realistic and include potential problems or negatives regarding the product, as customers will be more likely to trust your review and then buy the product based on this information.
How To Market your Affiliate Site
Post your article's URL on a social tagging site such as Digg.com and Reddit.com, or any other website to which you are a member. Post the article under a relevant topic, as you want the right people to read the article.
Trade links with other sites on similar topics.
Post comments on related blogs with a link to your affiliate article.
Tips & Warnings
Benefits of affiliate marketing: No warehousing of products; No tracking inventory; No shipping; No returns to process. The company of which you are an affiliate takes care of all the details of the order; all you need to do is drive sales to the company's website using your affiliate link.
Marketing is key – don't assume, "if you build it, they will come." Make sure to promote your affiliate webpage wherever and whenever you can!