Prerequisites:
- A Seller Central Account - Click Here to Sign Up
- Your MWS Merchant ID, Access Key, and Secret Key if setting up Pay With Amazon
Setting Up Login With Amazon:
Step 1: In your store's admin panel go to "Tools" > "Apps & Addons" then click on "Login and Pay With Amazon" on the resulting screen.
Step 2: In another tab go to the application screen in your Seller Central account, click on Web Settings. Then click on the "Edit" button. You should see this:
Step 3: In your admin panel, you should see the following text box.
Copy the URL in that text box and paste it into "Allowed Return URLs" in your Seller Central Web Settings.
Step 4: Paste your store's URL in to the "Allowed Javascript Origins." Example: https://www.yourstore.com
Step 5: Copy your Client ID and Client Secret from Seller Central in to the "Client ID" and "Client Secret" text boxes in your admin panel.
Setting Up Pay with Amazon:
Step 1: In your store's admin panel go to "Tools" > "Apps & Addons" then click on "Login and Pay with Amazon" on the resulting screen.
Step 2: You will need to copy your MWS Access Key, MWS Secret Key, and Merchant ID in to the corresponding boxes in your store's admin panel.
Step 3: In another tab go to your Seller Central account's Integration Settings.
Step 4: Copy the URL in the "Amazon Payments IPN URL" text box on your store's admin panel. Use this as your "Merchant Url" on Seller Central.
Lastly, you'll need to paste in the following amazon button code into Themes > Edit Theme > One Page Checkout > HTML Editor:
<ac:visibilityarea id="phAmazonLogin">
<div class="panel">
<div class="pad-20">
</div>
</div>
</ac:visibilityarea>
If you're no sure where to place it, a good place is just below the ExistingCustomersArea visibility area like so:
<ac:visibilityarea id="ExistingCustomersArea">
<div class="panel">
<div class="pad-20">
<strong>Are you an existing Customer?</strong> <a href="/store/login.aspx" class="btn btn-default">Log In</a>
</div>
</div>
</ac:visibilityarea>
<ac:visibilityarea id="phAmazonLogin">
<div class="panel">
<div class="pad-20">
</div>
</div>
</ac:visibilityarea>
And here's and example of how that would look on the checkout page: