Amazon has an amazing program called Amazon Associates. If you have two thumbs - or even if you don't - you should sign up. It's easy, it's free, and you will get rewards. I shall explain how it works.
1. Go to this link. Sign in with your regular Amazon account information (and if you don't have an Amazon account, you can create one).
As you sign up to be an affiliate, they will give you a code. Mine is trpildau-20.
2. Now that you have your code, you can start using it. This is where the fun happens.
Let's say you're me and you've just released a book. I'm using my novel Strength to Endure as an example. The link to purchase that book is http://www.amazon.com/Strength-Endure-Tristi-Pinkston-ebook/dp/B00IU0TW9M/ref=sr_1_1?ie=UTF8&qid=1445708235&sr=8-1&keywords=tristi+pinkston.
That's a pretty long link, right? Well, for starters, we don't need that whole link. See that word "ref" there in middle? I highlighted it so you could see it easier. You only need the information in front of that word. Delete the backslash too so now your link looks like this: http://www.amazon.com/Strength-Endure-Tristi-Pinkston-ebook/dp/B00IU0TW9M
You can do that any time you want to shorten a link. Just makes things a little less messy.
Now I'm going to take my Amazon Associates code and put it on the end of that link. I'm going to hook it on there with ?tag=. So it will be product link, that little connection code I just showed you, and then my code. This is what the final link will look like: http://www.amazon.com/Strength-Endure-Tristi-Pinkston-ebook/dp/B00IU0TW9M?tag=trpildau-20.
I promise - this is easy. It just looks complicated for now because it's new information.
3. Okay, now that we have our link with code, this is what we post whenever we talk about the book. I post on Facebook that I have a new release, I send out a newsletter, I put it on my website - every single time I talk about my book, I use this link with this code. If a customer clicks on that link and purchases my book, not only do I get my usual royalty, but I also get a few cents' credit through the Associates program. At the end of the month, Amazon adds up all my cents and sends me a gift card to be used on the site.
4. But this is not all. Let's say my friend Katie Crabapple has a new release and I want to help her spread the word. I do the same thing I did a minute ago with my book.
I'd take her link, which is http://www.amazon.com/Teaching-Patience-Homespun-Book-3-ebook/dp/B0088H8OZ0/ref=asap_bc?ie=UTF8.
I'd whack off everything after "ref," making the link now http://www.amazon.com/Teaching-Patience-Homespun-Book-3-ebook/dp/B0088H8OZ0.
I'd throw my code on there, making it now http://www.amazon.com/Teaching-Patience-Homespun-Book-3-ebook/dp/B0088H8OZ0?tag=trpildau-20.
I would then post this link everywhere, telling them about my friend's new book.
"But wait!" you say. "I don't want to make money off my friends like that!"
Here's the thing. You're helping your friends by advertising their book, and not one cent comes out of their royalty. The credit you get comes out of Amazon's pocket, not your friends'. It's a win-win for you and your friend.
5. And it doesn't end there ...
Let's say Geraldina from Kentucky uses my link and buys Katie's book. For the next 24 hours, unless Geraldina clicks on someone else's Amazon Associates link, everything she buys will be credited to my Associates account.
That's right. Let's say she buys Katie's book, and while she's on Amazon, she decides to pick up some ice cube trays and a video game and a new pair of shoes. A percentage of each of those purchases will get credit back to my account, and I'll get a gift card.
6. So, how much money are we talking?
The more items you put your code on, and the more purchases are made using that code, the higher your percentage will be. Right now, I'm making 6.5% whenever someone purchases using my links. If I refer/sell another 33 items, my percentage will increase to 7%, and it will go up from there. (No, I didn't just use some crazy math skills. It's all laid out for me on the Associates site.)
What's cool is that when I look on the Associates site and look at my report, I can see a list of all the things that were purchased using the code so I can see where my efforts have been the most useful. I see lots of my own books on there, but then I also see things like crochet hooks and hangers, things that were purchased while the customer was also buying my book, and I can see that the code really does carry over to other things.
The fact of the matter is this ...
Everyone should be an Associate. It doesn't matter if you're an author with a product to sell - you can help other people sell their products, as I demonstrated above with Katie's book. The fact that I am an author is just icing on the cake because I can use the code on every single one of my books as well. There's simply no reason not to take advantage of this program. I saved up my reward gift cards for the last few months and applied them toward some Christmas shopping I did on Amazon last night, and it reduced my out-of-pocket expense by about a third. That's not bad, folks. That's not bad at all.
(My thanks to Kirsten Osbourne for teaching me how to use my Associates account. I had one for years, but had no idea what to do with it until recently.)