Just ride, man. Best advice I can give you when hauling arse down a trail is to look down the trail not at the front tire. Keep your eyes fix down the trail as far as you can and pick the line you want to ride, and just ride. Your bike lose control when you brake on a sharp turn, so if you feel you need slow down on a sharp turn, tap your brakes slightly beforehand.
80% of your stopping power comes from your front brake, with that being said, if you got slam your brakes on a downhill, hit both brakes at same time to avoid flying over the handle bars. Two fingers on back brake and one on the front should do it. I got hydraulic disc brakes, so it might be different for you depending on feel of your V-Brakes.
Lot of the trails I ride have drops, berms, rocks, roots, big rocks, big roots, steep downhills, steep climbs, et cetera. It's a good way to keep your stress level down. It keeps my stress down better than fishing. I guess all of those tournaments I fished in couple years ago stressed me out. lol.
P.S. I don't carry a hydration pack unless it over 15 miles and I haven't drunk a lot of fluid leading up to riding. I try to drink all of my fluids before riding then drink Gatorade after the ride.