I have been printing in 3D for a few years now, and I am taking advantage of the arrival of new coils during this period of de-containment to tell you about the measures I use to preserve them as best as possible.
When you receive a new spool of printing filament, the filament of this spool must be aligned (no thread passes over another), ideally distributed (each layer forms a straight line, perpendicular to the discs of the spool), under vacuum (or at worst, in a waterproof bag), and with a desiccant sachet.
The first two points show that your manufacturer has used a professional winder, which manages the filament correctly during winding. The next two show that he has common sense, that he respects his customers, and wants his product to be kept in good condition.
Vacuum packaging is the best to guarantee the long conservation of the filament before its sale. But the resealable bag (freezer bag style) is the best way to store it at home, after purchase. Still accompanied by its desiccant sachet.
I specify here that I only print in PLA. These measures should apply to other materials, but do not hesitate to correct me or complete me if I forget things that would only concern ABS, PETG, PA, etc. You can push the subject by reading Etude de la conservation des filaments pour impression 3D (in french) from Maker Shop.
When I receive a spool, was I saying, I start by neatly cutting out its vacuum bag, which I carefully store with its desiccant bag. I install the spool and print a staple. If it is a new filament, I also print a medallion so that I always have a sample at hand with the brand and the model. Finally if its packaging is neutral, I print a second medallion that I stick on the box with double-sided adhesive.
When I store a filament, I carefully remove the filament, preventing the spool from relaxing. I cut it at 45 ° above the bead created by the heater to facilitate insertion the next time. I cleanly rewind what was unwound and staple it inside one of the discs of the reel, as taut as possible. I put the spool in the plastic bag that contains the desiccant sachet. I put everything in the box, which I store vertically.
When I get rid of an empty spool, in addition to ensuring which waste goes to which reprocessing subsidiary, I keep a few plastic bags with their desiccant sachet in case I test a manufacturer that does not do things in the standards, allowing me to pack a new coil more cleanly. I do the same with a few boxes of neutral packaging.