Basically, you’re finding great links to related subjects, sharing a small part of the article at each link, and making sure your reader can visit that link easily.
Then, you explain why you’ve included it, so your post is content-rich and original, not just a bunch of links. (Well, a few sites like Drudge Report have been successful listing only links, or minimal added content, like Fark.)
One of my favorite, geeky articles about what makes curated content work is this one by Robin Good. I actually printed that and put it in one of the how-to notebooks on top of my desk.
If your website features books or movies, you could create a curated article with a relevant interview (printed, audio or YouTube) linked in your post or even included in it.
I’m a fan of desktop curation software called CurationSoft. (I have the pro version, but you can try the free version to see how it works.) CurationSoft is the only curation software I actually use. For my purposes, it’s a little more robust than something like, say, Content Buddy. (I’m not sure if that’s still around, or even supported, as of 2015.)
What to do with curated content
If you’re adding just a single blurb/link, you can include it above or below the Amazon product description.
Otherwise, I like to create a separate post with the curated content. Not only is it a magnet to attract (and keep) readers, you can use that post to link to your Amazon product post, and vice versa. This gives your site more depth.
Once you develop the habit of adding curated content, it’s a breeze to assemble. Or, if you’re someone (like me) who loves “ooh, shiny!” trivia and information, it can be fun. However, there can be a learning curve. Have patience!