depends on the type of finished material you want. brain tan produces the softest type and can be done with other materials than brain. tanning actually refers to hard leather, like a saddle. it requires tannin from tree bark like hemlock, oak, cedar etc. . great for quivers . every method of tanning takes a lot of work. brain tanning can be done wet or dry. i prefer wet. dry is probably easier as far as the process itself goes.
to do the dry process first remove all the fat and meat from the flesh side of the hide. a straight piece of metal with a flat edge will work to remove this stuff along with a 6" or larger diameter tube. a debarked tree will work but in a pinch 6"pvc pipe works great. . next soak the hide for a few days in water, a stream is best but it can be done in a bucket. you just have to change the water a couple times a day or bacteria will build up ruin the hide and possibly get you very sick. if you can pull out the hair with your fingers its ready. remove all the hair with the scraper. now that the hair is removed you have to build a frame to lace up the hide. 2X4 nailed into a 7'X5' frame will do. you need to lace the hide to the frame. cut an incision about 1 inch in from the edge of the hide every4" or so all the way around the hide and run string from each hole to the frame. this allows the hide to dry perfectly flat. gotta go bring my kids to a party i'll finish up when i get back