here is the alum and salt method straight from Field and Stream magazine
Tan the hide
Tanning a deer hide with the hair on is work, but manageable. Here's the drill: Stretch the skin over a two-by-six. With a dull knife held at 90 degrees to the surface, scrape off all remaining muscle, sinew, and membrane. Rub copious amounts of noniodized salt into the flesh side, roll it up, toss it in a plastic bag, and put it in the freezer. Two to three days later, let it thaw, flesh it again, and wash out the salt.
Prepare a tanning solution of 4 gallons of water, 1 pound of granulated alum, and 1 pound of salt. Soak the hide for a week, stirring once a day.
Remove it from the tanning bath and squeeze it dry. Lather the flesh side with neat's-foot oil; let this soak in for a few hours. Stretch the wet hide over a hard, straight edge such as a sawhorse or table, and work it back and forth, as hard as you can, to soften it. Use a rounded dowel or butter-knife handle for the hard-to-reach corners. If you think you're finished in less than eight hours, you're not.