To get started with Amazon affiliate marketing you will need to sign up with Amazon Affiliates. Then subtly market products on your site that are relevant to your niche and will be of interest to your audience. Make sure you only endorse high-quality products. If your visitors make a purchase on your recommendation but are not impressed with the item, you could quickly lose followers.
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.