Boveda packets work very well. Be sure to get the 62% packs.
http://www.amazon.com/s/ref=nb_sb_noss_1?url=search-alias=aps&field-keywords=boveda+62&rh=i:aps,k:boveda+62
I respectfully disagree that 3 days should be max. Living in a very humid climate like the NW, I find a week is about right. I even put a very small bath dehumidifier on a 12/12 cycle which helps start the cure a little on the branch.
* 12/12 cycle on the dehumidifier lets the outside get dry while it's on, then the moisture comes out of the stems when it's off making the buds feel moist again. Like burping on the vine.
The other hint I would like to share is don't get caught up in these "rules". The amount of time needed to hang or even to cure, varies a great deal depending on time of year, weather, strain, grow success, my point is; there is no right or wrong way to go about.
I have always been confused by the common assumption that the worst thing you can do is over dry. You'll never get a good cure if it's not dry enough. You can't be concerned with weight over quality, that's just lame.
Maybe you over dried it, but honestly, maybe not. I'd rather have pot that burned quickly into clean white ash, then moist pot that leaves those little black coals that never quite burn. If you're seeing little black coals, quests what? You're weed isn't cured.
Turbobuzz is correct, curing is at least as hard as growing, and the final most crucial two weeks of the grow are the hardest to execute correctly.
But it seems to me the OP is on the right track. Don't under dry.