I was having problems with this.....but I finally got it last night
Create a new account on my xbox and start FIFA. (You can end/skip/forfeit any matches it puts you in)
Go through the process of setting up an EA account for this gamertag.
Go into Ultimate Teams, go through the tutorial stuff until you are at the stage where you have control to do whatever you like.
Go to the SQUADS tab
Choose ACTIVE SQUAD (there may be more tutorial stuff, i don't remember)
Top right of the screen should say
and choose to Share your Squad
Go back to your main account and gift an item to your new gamertag.
Worked first time for me. Hope it helps