often get self set hollies at my parents, (they've some holly hedge) and i'm aiming for a holly hedge, so they get hoiked out!
after taking them up, (they were only couple inches high) they went into a pot and then planted them out after a few months. they were outside all the time, though. i must admit that when i took them out of my parents' garden they went into pots with just the garden soil surrounding them, so i wasn't particularly kind to them at all. they're going very well in pretty poor soil now, considering i had the impression holly was a slow grower.
so!-i would pot it up, keep in pot for a little while, harden off like aqui says, and plant out this year.
but others may do different.................................!