I buy at least 2 packs of strings at once. I always store unused strings in their original package with a pack of silica gel thrown in. The silica gel helps to keep moisture and crap out keeping your strings fresh. I also use it in my bass cases, about 3 silica gel packs per case and I change them about once a year. You can get silica gel in just about anything but mostly in clothing, especially all kinds of leather goods. You can also re-use it by putting it into a hot oven for a few minutes but I have never done this.