All gifts and keys will be sent in real time via Steam chat only - the reasons for this with official Support posts can be found here :

http://www.steamgifts.com/discussion/GeDfy/failure-to-activate-and-regifting#AzVn0tf
http://www.steamgifts.com/discussion/27ziC/just-so-you-know-there-is-no-such-option-as-intentionally-taking-the-not-received#2b03qCr