Best venison
The best venison I have had have been southeast Minnesota younger bucks that have been feeding on corn and apples from the local orchards. Deer that not been run all day do not have lactic acid built up in their systems. I think a deer being in shock for some time also alters taste.
But most importantly, take care of the deer after the kill. Try to shoot it in the chest cavity or neck. Make sure you kill it quickly. Field dress it immediately being very careful not to cut the bladder or intestines. Don't wash out the inside as the water can flush bacteria into the meat.
I don't split the chest or cut the neck, but I do place the deer on the snow open cavity down to let most of the blood drain. Then I put the deer on its side and prop open the deer with sticks to cool as quickly as possible. When the temp is below freezing, you can hunt the rest of the day and hang the deer in the evening.
I suggest hanging the deer by the rear legs. This stretches the muscle fibers and allows blood to drain from the legs and loin. I haven't aged deer as I don't have a locker, but I let them hang at least over night or two days with the skin on when it is cool. Try not to let the deer freeze, however.
Head-down hanging makes skinning easier. Start at the back legs and peel down cutting the fascia. If you are careful, you won't get much hair on the carcass. You can saw the head off at the neck. The back loins come out easy, and the back legs stay up off the garage floor until you are ready to take them off the hooks.
My girlfriend's dad (future father-in-law) worked as meatcutter several years ago. My dad is a retired biology teacher. Removing the meat from the bone, fat and connective tissue and then cutting it across the grain results in perfect cuts of meat.
Both stress using clean, sharp knives and a clean work surface. I use clean plastic sealed Rubbermaid tubs to sort meat and store it in the fridge until packaging. One pound of steak is sorted, wrapped in Cling wrap, wrapped in commercial plastic-backed freezer paper, labeled and stored in the deep freeze. We use a commercial electric meat grinder and make our own hamburger. We know exactly what goes into our burger and homemade sausage!!!!!!!!!!!
I will never take a deer to a processor. Some just let them sit stacked up outside where rodents knaw on them. They just band saw the meat with fat and bone chunks and wrap it. No wonder why people say deer meat tastes bad. Remember to wash your hands a lot and use clean plastic sheeting on your work tables.
Clean, Clean, Clean means great venison.