A fellow in this area rolls the skin up backwards --loosely-- puts it in a coffee can and fills the can with automotive antifreeze.
When removed, (after a couple of days) the skin is quite green colored....he says he hangs it on a board for awhile and the green color gradually leaches out/goes way and that the skin is perfectly soft and preserved.
I dunno.....
other than that......
http://www.taxidermy.com/ ...then /Products ..then /Reptile tanning kits
True-Tan Reptile & Amphibian Tanning Kit
Even a beginner will be able to tan a snake skin like a pro when using this easy-to-follow, two-step tanning method. The instructions explain how to skin the snake using a sharp knife, scissors, and puffed borax. Next the dry chemical is mixed with water and the skin is left in this solution overnight. The hide is stretched and pinned flat to dry while the tanning oil is periodically brushed into the skin. The resulting tanned hide can be made into a flat rug wall hanging, a belt or a hatband. This kit will tan up to two large snakes. Cannot be shipped by air.
True-Tan Reptile & Amphibian Tanning Kit Includes:
* 3 oz. Puffed Borax
* 1 cup dry Reptile Tanning Chemical
* 8 oz. Reptile Tanning Oil
* Snake Skinning and Tanning Step-by-Step Instructions
Code Item Description S.W. Price
HK20 True-Tan Reptile & Amphibian Tanning Kit 1 lb. 17.95