Always double box and wrap your items good.
Write a detailed description
Very importnat - note all issues with the sneakers such as tears, rips, factory blemishes, yellowing etc.
Post the max. allowable photos which is currently (12 ) for the free accounts
Post clear, detailed photos.
Post a front, left side, right side, toebox, back side, sole, insole, shoe label - inside shoe, label on box, entire box
Always do Buy It Now listings. New buyers who do auctions generally don't do well
If your Buy It Now sneakers are not moving, consider dropping the price every few weeks. I like to drop the price every two weeks by a couple of bucks
Take a photo of the package after you get it ready for shipping. I like to message it to the buyer alerting them the package is on the way and letting them see (for piece of mind)
the shoes were double boxed