Recycle Steam Community items like Trading Cards, backgrounds, and emoticons from your Inventory into Gems and use them to bid on games up for auction. The first auction round ends on 15 Dec @ 3:45pm with a new round ending every 45 minutes until the last auction round ends on 18 Dec @ 6:00pm. At the end of each auction round, the top bidder for each title wins.
Pro tip: Need more items to turn into Gems? More than 1,200 games on Steam drop Trading Cards just for playing them. Find out which of your games has drops remaining on your Badges page. Also, don’t forget to craft the Trading Cards into badges, the resulting emoticons and backgrounds have a higher Gem value. If you have nothing in your Inventory to recycle, you can also trade for Gems or purchase them on the Community Market.