Here's how to do it: (All photos are from Formal Fringe)
Insert the bottle inside one sock.
Fold over the extra length of the sock and use the other sock to tie around the neck of the bottle.
Tie a knot or a bow. Any will do.
And there you have it! See, told you it was real easy.
I suggest using long socks and those with adorable prints. As for the tag, I'd punch a hole and pin the tag on the sock with a safety pin.
Happy wrapping and happy giving! :)