Tanning skins consist of the following processes:

Wash the hide of all blood, or if dry skins are to be cured, soak them in water with a little borax added, until soft and pliable. 

Flesh the skin on a 4" x 2" board with rounded corners, using a carpenters draw knife, until all fat and membrane is off. 

Soak in half a cup of Formic Acid  (dangerous) per 5 litres of water plus 1lb of salt per 5 litres for 12hr to 48hrs depending on the thickness of the skin. This stops the skin shrinking too much during the process.

Now mix up the following solution in a non-metallic container:-

RATIO ONLY,- 1 gallon warm water, l lb Alum, l lb Salt, 4oz Chrome Alum (Dangerous - use rubber gloves and glasses.).
e.g:- 1 gallon minimum for Rabbits. Oppossums etc.
5 gallons minimum for Chamois, Goat.
10 gallons minimum for Sheepskin.
20 gallons minimum for Cow Hides, Bull Thar.

Put the hide in the solution and leave for two weeks or more until the hide is of even colour throughout. (Test by cutting a small cross Section). Stir the hide in the solution and stretch out the wrinkles every two days.

 Drain the skin, then wash in detergent and water, then in petrol.

 Stretch the skin on a frame. Paint a thin coat of., 1 part, Lanoline (sheep grease) - to 9 Parts Kerosene. Melt the lannoline- before mixing in the kerosine, making a very thin warm liquid. Dilute it with kerosene if necessary. 

When the skin is nearly dry. scrape with grubber, tyre lever or blunt instrument, to break up the fibres. Work the skin while it is drying until it is dry. First sprinkle with french chalk ballroom powder, fine sawdust or some similar substance, then sand with very coarse sandpaper or wire brush. 

The hair can be cleaned by a brisk rubbing with turpentine on a rag.