Der er ikke andet at gøre end at sælge hele accounten.
Hvis du ikke har brugt spillet endnu, så kan man jo lave en aftale om at sende spillet over steam når pengene er gået ind på kontoen... 
QuoteDisplay MoreWhat is a Steam gift purchase?
When you purchase a game on Steam, we offer the option to “gift” the item to anyone you choose, whether or not the recipient is a current Steam user. The recipient will receive the gift as an attractive e-mail card with a personal message from you and instructions to redeem the game.
A Steam gift purchase is a one-time transfer—after the recipient has activated and installed the game, it is a non-refundable game in his or her Steam games collection. Also note that you may only gift new purchases—you may not transfer games you already own. That’d be like wrapping up and presenting the toaster you’ve used every morning for the past year.
How can I purchase Steam Gifts for a different Steam user?
To give a gift to a friend or family member, locate the game you would like to gift on the Steam Storefront and then click the "Add to cart" button. Upon checking out, select the "Purchase as a gift" option to purchase the items in your cart for a friend.