When you climb a hill, aim to keep the power on over the top of it so you regain a good cruising speed before you relax and rest. You’ll have a far higher average speed and you’ll demoralise anyone trying to “race” you.
Finding out just how fast you can stop, lets you go faster for longer, so you’ll get to the bottom quicker. Choose the best section of trail for traction and anchor hard and fast as you can. Keeping braking to short bursts will also save your arms and your brakes from pumping up.
Look further ahead down the trail. Your head will pick smoother lines and you won’t be reacting to obstacles at point blank range. Concentrate on deliberately ‘flicking’ your point of vision further away from you as you ride.