Take good pictures. Some of the options below don’t require you to actually take the picture and sell the product, but for the ones that do, make sure you take a clear picture that makes your product stand out from the others. If you’re going to be taking a lot of pictures, set up a small “studio-like” area in your home with a backdrop and proper lighting to really make your pictures come across as professional. And of course, you’ll want a good camera too.
Amazon’s affiliate program is the most popular of them all. I don’t participate myself (yet) but the majority of affiliate marketers I know use Amazon because… it’s Amazon. You can review products you have used or write tutorials (eg. how to connect computer to TV) and drop an affiliate link to an HDMI cable… just a couple examples. You may want to build relationships with the manufacturers so you can get products before they’re released – giving you time to create a review before the product is launched and capture sales during peak buying times.
Find a profitable niche. Starting with your interests, write down as many niche ideas as you can. Think about topics people might search online. Ideas include passions (like surfing or body building), fears (like spiders or speaking in front of crowds) and problems (like getting out of debt). Do keyword research to see it others are interested in the topic. Find out if a domain name is available that matches the keyword 100 percent. 
Nice work Laura! This is going to be a great series. I'm working my way through SEOmoz's Advanced SEO Training Series (videos) Vol. 1 & 2 to build upon the advice and guidance that you and your team provided to me during my time at Yahoo!. Now many others will benefit from your knowledge, experience and passion for SEO strategy and tactics. Best wishes for great success in your new role.
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Every follower should be aware that the links on your site could lead to a commission of some kind for you. Even if you are making a simple social media post, you need to disclose that the link is an affiliate link in some way. If you do not disclose this fact, then you could out of compliance with guidelines issued by the Federal Trade Commission.
Learn how it works. An affiliate marketer embeds her own unique affiliate link in her web page or blog. This link does not have any impact on customers, and it does not alter the price of any products/services being offered by affiliates. However, any time the customer makes a purchase after clicking an affiliate link within a specified time frame, the marketer gets a commission from that sale. How much you earn will depend on each affiliate's prices, commission percentages, and the number of sales you're able to initiate on a weekly or monthly basis.
Consider selling in lots. A lot is a collection of similar items that is sold in a group. For example, if you have a collection of books, magazines or similar pieces of jewelry, consider selling them all at once in a lot. You many not make as much money as you would have if you sold each item separately. However, the items will likely sell more quickly in a lot than they would individually.