Try and shoot a cow under 4 years old. Don't shoot a cow over that! Or you'll be eating shoe leather. Or 400 pounds of hamburger.
We have taken a few bison cows. Jackson Hole refuge hunt, and a few of of ranches.
If you are going to get the hide tanned do it hair on, most of the leather maker type outfits will screw you over. We have not had a chrome tanned hide come back we liked.
We opted for the bug cleaned skull on them and they look great. Then again, you won't want to shoot her in the head.
As far as season, do it during Christmas time. She will be as prime as she will get then.
You personally can not legally sell the meat yourself, unless you are a USDA licensed butcher, and the cow was inspected prior to the hunt. Big fines!
We eat a lot of buffalo burgers, buffalo spagetti, jerky, salamis, sausages, buffalo meat balls, out of the burger. Great tasting stuff. Older animal will be tough, don't let anyone tell you different.
The younger cow we shot had great steaks.
Typically we were shooting 1 a year for the meat, but we got a bit backed up and now it's 1 every 2 or 3 years.
YOU CAN NOT LEGALLY SELL THE MEAT! FEDERAL FINES!