This article is from the Mountain Biking FAQ, by Vincent Cheng.
-find a couple of step to practice, then move on to steeper and shorter
steps
-assume the downhill position. Butt off saddle, weight back, keep arms
and legs loose
-point the wheel perpendicular to the ground and ride straight down
-Do little braking if needed, but you do not want to lock up the wheels
while they are in the air
 
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