Self brain tanning is LOT of work, but it is a very neat process and fun to learn. It can be done in stages over the winder, so that helps. I've never done a bear, but I have done both Elk and Mule Deer - both hair on and off (I think hair off / buckskin is easier)

You would need to have your fleshing beam, hide stretcher, large pots / barrels & fleshing knife ready to go before the season. I'd probably only do it again if the hide came from a DANDY trophy bear.

Have fun,