i would stay away from metal containers. ive never researched the main reason but i do know from handling metal in the past that it leaves a nasty smell on your hands so i feel it would do the same to your flowers.
best basic method i have heard (doesnt need the humidor packs if you are saving money)
Large mason jar, fill it 75% full (not packed)
store this jar (i prefer in a crown royal bag added extra darkness)
in a nice dark cupboard that wont be opened often.
Open and take the lid off the jar once every day for a few seconds some will go minutes.
This is referred to as Burping.
However this is all done after you have
Cut and Trim the major fan leafs off leaving the smaller sweat leaf on so they dont over dry, but your fan leafs wont dry up and cover your entire nugs locking in that wet smell (hay smell)
hang your plants to dry for a week or so depending on how soaked your soil was before you cut and how thick them nugs become. if waited till the medium is dry it wont take as long to cure but still will take some time.
Then go about ur curing in jars.
I&i
hope this helps and i hope others chime in as well.
as i know mines far from the only method and u need more methods to mix together!!