There are eight steps to follow when you think about selling on an online auction. The competition is serious and your product can get lost in thousands of other listings.
Step 1: Select the site that is best for your product. You shouldn't choose an auction that already sells your same product or something similar. It's all about making the most profit!
Step 2: Choose your product. Will it be a one-of-a-kind product or something you can sell in bulk? You have to consider the demand for your product.
Step 3: Choose a listing option. Your product can be shown in a regular listing which is the most common. You can do reserve price listing, which means you have reserved the item at the price that you think it should sell for. You can also use "Dutch auctions" or get your item featured through the site's homepage.
Step 4: Choose a category. It should be specific enough that your item can be easily found.
Step 5: Create your ad. Be specific and try to motivate your bidders. Don't forget photos! People don't want to buy what they can't see.
Step 6: Establish trust. Keep a good feedback rating by delivering exactly what you advertised in a timely manner. Answer questions immediately and be honest.
Step 7: Get exposure. Post your ad in other places and give good customer service because word of mouth is powerful.
Step 8: Test it! Always keep your listing updated and see what works best.
Source:
http://www.entrepreneur.com/encyclopedia/online-auctions