A question about gifts

hello i was buying a title on steam and the delievery gave me three options with the 3rd being "Store the gift in the inventory to send later" with sub text "Gifts become tradable after a Steam account has been in good standing for at least 90 days. This gift will become tradable on 20 January 2013. See the Steam Trading FAQ for more information."

my question is if i buy it now and make a giveaway will i be able to send it to the winner (if so how) or will i have to wait till 20th jan and then make a giveaway?