Affiliate marketing works in conjunction with several other online advertising mechanisms. This is the case because affiliates will often use these platforms for marketing purposes. Some of the mechanisms include search engine optimization (SEO), e-mail marketing, paid search engine marketing (PPC-Pay Per Click), display advertising, and content marketing. At the same time, affiliates can also appropriate less traditional advertising methods. An example would be publishing reviews of services or products.
If your niche doesn’t allow you to promote or build premium products (anything over around $100 per unit) then think about getting a solid mix of offerings and building it up over time. I remember Darren Rowse saying that initially Amazon Associates was a really small source of income but over the years it has really started to add up. Think eBooks, affiliates, consulting, books, etc. and you’re starting to build an income stream.
Once you setup your account on AdSense you will be given a code to add to your blog. This code will automatically display advertisements on your blog from companies who are part of Google’s advertising network. You may see ads from small companies related to your topic, or you may see ads from large companies that are completely unrelated to your topic.