Incidentally the salt to use is DVP - Dry Vacuum Packed - which is sold in 25kg bags by your agric merchant for a few £s. Once you have covered the skin side with salt (paying special attention to unrolling the edges, opening out the legs etc) , leave it for a week or so, topping up the salt where it goes pink. Fluid will drain off and once this stops you can shake off all the old salt, re-cover with a light fresh layer then roll and send the skin off to the tanners. The best time to do this is in a dry cold autumn so the air humidity is low, but Nov is the latest to do it because any later and the 'rise' has begun, so the wool comes off during the tanning process
I lay my skins on a sloping surface to help the liquid drain off, with old straw to catch it on the floor. The wet straw can then be burned. You can stack the skins to about 4 high, swapping them round once halfway through the salting process.