I'm no mountain goat, but I know a few tricks (even if they don't help me, they may help you):
1- drop your forearms low, try to keep them parallel to your toptube, this way when you use your arms to stabilize your upper body as you pedal hard, you will pull 'back' and not 'up' on the bars. This helps keep the front wheel planted and your chest low.
2- drop your heels. This one is a little weird sounding but it actually works for me. Try to think about keeping your heels below the pedal spindle as you pedal through the bottom of a pedal stroke, it keeps your weight down slightly and gives you a little more power.
3- ride in a bigger gear. This one is really hard sometimes, but it's easy to 'loop out' in the granny, if you can pedal a harder gear you can carry a little more momentum and apply power more smoothly which helps out HUGE on roote and rocks.
4- time your effort. When you see a rooty step or ledge coming try to give a hard effort before (a few pedal strokes) you get there to increase momentum and allow you to concentrate on where you weight is as you clear the object. Get the front tire up and over/on- quick and strong half pedal stroke with your butt off the saddle, compress the rear suspension, then move your weight forward and up (drive your pelvis from just above the saddle toward the stem/ head tube) as the rear tire hits, this forward lunge + suspension rebounding will pull the rear tire up and over. Once your over you can reapply the power, avoid pedaling hard as the tire touches or you will spin-out and lose all forward momentum... and mash yourself into the stem and hbars.
5- Learn to hover. Try riding with your butt hovering just over the saddle, it's hard at first but it can allow you to put lots of energy into the pedals in rough terrain while keeping the rear tire hooked up.
6- stand all the way up and wrench on the handlebars like a sprinter in the TdF. It massively inefficient, but for short burst and quick uphills it lets you stay in a big gear which minimizes wheel spin and let's you stay moving fast which makes techie stuff much easier.
7- Think like a single speeder. It's all about conservation of forward momentum, accelerate into climbs, don't soft pedal and slow down until your granny gear can be pedaled (I'm guilty of this) accelerate and attack the hill. (once your over the hill stop thinking like a single speeder, use your damn gears, SS'ers are idiots).
Hope some of this helps you out. Knowing what to do and being able to do it when it feels like your eyeballs are about to pop out of your head are, sadly, two separate things.