Jeans, I keep my hackles in plastic boxes with a few moth balls. I have had some necks for over ten years. As far as preparation goes, you only have to prepare a hackle for the fly you are tying at the time. No other preparation is needed. Some times when I keep fresh gamebird hackle or quills I will let them dry for a few days with a bit of salt on them to ensure that any flesh which may be on them dries up. Then just box em' up and use them when needed.
Regards, Bill