Like many people who are into collecting, there is the special collection. This is the stuff I hang onto or what I call 'The Retirement Fund'. I have a large collection of mid century textiles, I just love them.
This one is a Heals London by Dinah Marsh. Late 60's. It's in excellent condition but it did have stitched selvedges. I do unpick stitching on my fabrics and press before storing them.
I store my fabrics in acid free tissue and soft fold them to prevent permanent creases. This is really important if you are storing acetates, silks and brocades. You can create nasty hard to remove creases if you don't store properly. I also store all my fabrics in a linen press or hall cupboard. My house is a 60's one so it has the good hall linen presses. (the rule now is if it doesn't fit in the hall press, it has to go) and I take them out and refold every 6 months or so, again, this is to prevent permanent creases and age spots. It's a good idea to air textiles every now and again. Plastic boxes are ok for short term storage, but fabrics need to breathe.