Giveaway question

Hello today i made this giveaway : http://www.steamgifts.com/giveaway/I8mQK/the-ship

and i have 1 invitation in my inventory so i wonder how do the winner will get it ? it will automaticly send the invite to the winner ? or i will need to send him the invitation by my self ? and if so how do i see who is the winner ?

:) so many questions but i have to know how it works .