Most articles about storing sails just say to roll them up rather than stuff them into the sail bag, but is there a correct method for rolling them?
The best way to store a sail for the off-season or any prolonged period of time, once the sail has been washed and completely dried, is to fold the head of the sail down at the top quarter. Then start at the folded area and begin rolling the sail down to the foot. (If the sail has battens and you're storing it for a long time, it's best to remove the battens first before rolling.) The same procedure should be used with genoas, jibs, or mainsails, and mizzens too if you have one.
If you cannot roll the sail because of storage issues, flake the sail in an accordion fashion, starting at the foot and progressing to the head of the sail. Once it is flaked into a narrow strip, begin at the luff and roll the sail toward the leech so that it fits into the original sailbag. Again, if there are battens in the sail, you'll first need to remove them.
Once you've got your sail rolled or flaked and in its bag, the best place to keep it is in a cool, dry place, free of outside light sources. For more detailed information on sail care, have a look at Kathy Barron's article Sail Care and Cleaning, here at SailNet. Here's hoping that this information is useful.