Well, I made a couple of blankets when there was still no grandbaby...
Anytime we store projects for a long time we should get them out and refold them periodically. I would get a nice sturdy box, like maybe what a pair of boots comes in and loosely fold the project in some manner. Resist the temptation to flatten it out, keep it fluffy, and then stick it on the top shelf of a closet and maybe once a year or so, take it out and refold it in a different manner.
If it wouldn't get crushed, instead of a box I'd also consider rolling it loosely and putting it inside of a pillowcase. Again, good closet top shelf storage
