Action Details
Requirements and how-to articles for Amazon's action:

Create a new listing for a product you wish to sell on Amazon. You can also include different variations of the same product.

You need this to get it done:

Choose the category which best suits your product.
Product ID
To list your products you require a unique identifier for your product such as UPC, EAN or GCID. You can request exemptions to list products that do not have standard product IDs for certain categories.
Product Name
The name of your product. Maximum of 100 characters.
Brand Name
The name of your brand. To list your products after your brand is enrolled, enter the brand name exactly as you submitted it for brand approval, and specify a unique value for the Key Attribute that you selected in the brand registry application. You can always edit the product details later in "Manage Inventory."
The manufacturer of your product.
Manufacturer Part Number
The manufacturer part number for your product.
Advanced View Fields
In advanced view, you can enter the colour, colour map, size and size map of your product. This is recommended if you are selling different variations of your product.
If you are planning to add different variations of your product, you can list them here. Each variation also requires its own Product ID.
The condition of your product ("New"/"Like New"/"Very Good"/"Good"/"Acceptable") (See selling policies and code of conduct for more details on condition labels.)
The price of your product.
Product Images
Listings that are missing a main image will not appear in search or browse until you fix the listing. Choose images that are clear, information-rich and attractive.
File format: .jpg is preferred, but may use .tiff and .gif
Dimensions: Must be at least 1000 pixels on the longest side and at least 500 pixels on the shortest side. Must not exceed 10,000 pixels on the longest side.
Products must fill at least 85% of the image and must only show the product that is for sale, with few or no props and no logos, watermarks or inset images. Images may only contain text that is a part of the product. Main images must have a pure white background and must be a photo (not a drawing.)
Product Description
Describe your product in detail. Maximum of 2000 characters.
Key Product Features
List the key features of your product. Maximum of 1000 characters.
CPSIA Warning
The Consumer Product Safety Improvement Act of 2008 and the Federal Hazardous Substances Act require the display of appropriate cautionary statements relating to the choking hazards of toys and games intended for children 12 and under on the product packaging and in certain advertisements.
Keywords (Intended Use)
Keywords relating to the intended use of the product (e.g. baseball, Halloween, kitchen.)
Keywords (Target Audience)
Keywords relating to the target audience of the product (e.g. teens, toddlers, cats.)
Keywords (Other Attributes)
Keywords relating to the other attributes of the product (e.g. antique, cordless, waterproof.)
Keywords (Subject Matter)
Keywords relating to the subject matter of the product (e.g. Christmas.)
Keywords (Search Terms)
Keywords relating to terms which users may search to find products like yours (e.g. electric.)
Keywords (Platinum)
These are only available for Platinum level merchant accounts on Amazon, and allow the seller to customise which products customers see when visiting their storefront.
Requirements missing or found errors? Report

How-To Articles
A list of useful links for you:

Amazon Seller Central - Add a Product Tool
Information about adding products to your Amazon store.
Amazon Seller Central - Selling Policies and Seller Code of Conduct
Policies which all sellers must adhere to when listing products on Amazon.
Amazon Seller Central - Product Guidelines
Guidelines for different types of products.
Link missing here or found errors? Improve How-Tos