This is a small but still irritating challenge for most closets. If you are anything like me, you do not keep the foam inserts that come with the boots you purchase, however that would be the ideal!
It is very important to keep your boots in good shape, therefore if you simply take your extra grocery bags/target bags, etc. (about 3 to 4 in each boot, this will keep the boot standing straight up, and reduces the look of creases and wear on your investment. Thicker magazines, rolled up, work well too!