When you join an Affiliate program and choose the products that you want to sell, sellers provide you with a unique affiliate code that you can use to refer traffic to the target site. Most affiliate programs will offer ready made text links, banners and other forms of creative copies whereby you only have to copy the code and place it on your website to start referring traffic. When interested visitors click on these links from your site they get redirected to the product site and if they purchase a product or subscribe to a service you as the referrer make a commission.
To refresh your knowledge you might remember that context ads earn you money for each person who visits your site and clicks on the ads. The ad network automatically generates the ads and you insert them into your site just by copying a small piece of code. The biggest context ad network is Google AdSense, so a lot of people (including us!) will use the word "AdSense" when they're really talking about "context ads" in general.
Affiliate networks administer programs for individual merchants, handling all the work involved, while generally providing tracking and reporting capabilities to their affiliates to help them keep tabs on their revenues and determine which products or services are producing the best returns. These tools can be helpful to an affiliate in fine-tuning the line of products she decides to promote on her site and, ideally, increasing revenues as a result.
LabradorTrainingHQ.com is a site that I came across when doing some competitive research for Perrin's affiliate site.  They compete for some of the same keywords, and it appears that they are monetized by the same methods (Amazon Affiliates and an Affiliate Program with Chewy.com).  This site gets more traffic than HerePup.com, but it's still another example of a smaller website doing very well.  This is a WordPress site, with a generic template/theme and (there are free themes that look just as good) it's more in the form of a Blog than an actual media property.
Affiliate marketing allows its marketers, or “affiliates,” to take their income into their own hands. This strategy is, in some instances, referred to as a form of “passive income” for those who endorse products. By this, we mean affiliates aren’t always actively selling to make money. They put their strategies in motion and any sales that come through their site drive income.

We've partnered with The Foundation for Learning and Youth Travel Education (FLYTE), a nonprofit organization that empowers youth living in underserved communities through transformative travel experiences. FLYTE teaches that we are more alike than we realize. By bridging the gap between fear and understanding, FLYTE empowers future generations by connecting them to the world.
Be sure to check what kind of customer support you can expect from your affiliate program once you have signed up. Do your research online and if possible, speak to other sellers using the program to get their thoughts. Can you speak to someone via phone or Skype or do you have to wait 72 hours for email responses? Be clear on this because trust me, you will need support at one point or another. 
This site will not get penalized because they are within Google Adsense guidelines for number of ads. You are allowed 3 block ad units (this site has 2 at the top and one in the sidebar). You are ALSO allowed 2 link units (in addition to the 3 ad units) – for a total of 5 adsense units total. The link unit on this site is at the top where a regular navigation bar goes. So in reality, this site could actually have 1 more link unit on their site that is not shown in this screenshot. Hope that helps.
If one of your readers clicks on the link and goes on to purchase the book or ebook, you’ll receive a percentage of the sales price (it varies from retailer to retailer, but 5-7% is about average for books). You’ll also get a cut of other purchases the buyer may make during that shopping trip (with booksellers, there’s usually a 24-48 hour window during which you’ll get credit).
Once you do move forward, don't resort to simply throwing up a handful of banner ads and call it good. All successful content-driven affiliates will tell you that deep integration of your marketing into your content is the most successful strategy, most of which can be accomplished by looking for affiliate tools outside of the quintessential and tired banner ad.
The topic you choose must have enough depth that you can create a lot of content for it. This is important for building an authoritative site, for search engine optimization, and most importantly, for the end user. If you don't have enough content about a topic, you're not going to be taken very seriously as an authority on the topic and it's unlikely you can convince someone to make a purchase from you. 
Now you should have a pretty good idea of what niche you are going to get involved with. It is possible that you haven’t narrowed the list down to a single topic area, but you probably have found a few ideas that you feel real good about. Now at this point, it’s important to get an idea of how much money you can potentially make in your chosen niche. ClickBank is a great place to go to that search. First you browse top products in your category. If you don’t find any offers, that is not a good sign. It could mean that no one has been able to monetize that niche.
In February 2000, Amazon announced that it had been granted a patent[14] on components of an affiliate program. The patent application was submitted in June 1997, which predates most affiliate programs, but not PC Flowers & Gifts.com (October 1994), AutoWeb.com (October 1995), Kbkids.com/BrainPlay.com (January 1996), EPage (April 1996), and several others.[9]
Some bloggers are uncomfortable with the idea of including advertising on their site, especially if that advertising doesn’t bring a significant return, and affiliate marketing isn’t for them. However, even if you’re comfortable with including advertising on your site, for the vast majority of book bloggers, affiliate marketing is never going to be a large, reliable source of revenue. As in, the chances of being able to quit your day job and live off your earnings are slim to none. However, if you have the attitude that you might receive the occasional small bonus in your bank account, then go for it! Your earnings might even get you a lil’ somethin’ special next time you visit the bookshop. 

 The idea behind the book is to build a lifestyle business by using the right strategies. You'll learn how to identify the parts in your business that generate the most results, automate almost every aspect of your business, and how to outsource almost every task. It will give you a unique perspective on how to approach your online business by working smarter, not harder.
The thing I like the most about the site is the way it feels.  All of the Amazon affiliate links are extremely well integrated, and they've done some custom design work to make some of their images feel interactive.  Another trend here is that the owners of this site, own similar sites in several other niches.  You can tell which sites are owned by the owners of this site when you look at the bottom of the site and notice that they link internally to their other web properties.  This is becoming a popular trend, with the folks over at DigitalMarketer.com doing the same thing with some of their projects, like SurvivalLife.com and DIYReady.com.  It's hard to estimate the total revenue for this site, but because the call-to-actions on the site are so good, it would not surprise me if this site was doing over 70K per month in Amazon Affiliate income every month.

This doesn’t mean you only sell one product. This means you build out a brand by selling varying yet adjacent products. Over time, your consumer network might consider you a go-to for which type of vacuum they should buy. Additionally, some industries pay more than others. Especially if the product is a harder sell, affiliates may get a higher cut than they would for a product in higher demand.

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