Set up your Podcast at Amazon Music by clicking here.
Click on "Add Or Claim Your Podcast" and follow Amazon instructions.
Before uploading your podcast you need to have an Amazon account. If you don't have it yet, you can create it here.
Click on "Sign in With My Amazon ID", then fill in your user data and log in. A screen like the following will be shown where you have to put your RSS.com feed like https://media.rss.com/myRSSpodcastshow/feed.xml.
In this part you have the option to choose which country your podcast is most suitable for (This is optional). When you finish just click on the "Submit" button.
After confirming that all the information is correct and accepting the Amazon terms of service, click on the "Confirm Email" button.
You will receive an email like the following, click on "Confirm Ownership"
Done! Wait for approval from Amazon. In case your podcast is not accepted we suggest you contact the Amazon podcasters team at firstname.lastname@example.org