This article is from the Skydiving FAQ, by Barry Brumitt with numerous contributions by others.
It a nutshell, you can't -- unless you're already a very experienced
skydiver.
"Skysurfing" or "Skyboarding" refers to skydiving with a small board,
similar to snowboard, attached to your feet. This allows for some
radical maneuvers in freefall. However, such jumps should only be
attempted by expert skydivers, and preferably after long discussion
with one of many skysurfers who have experience. Some board
manufacturers and experienced skydsurfers offer instructional classes
or videotapes.
BASE jumping involves jumping off of fixed objects (like Buildings,
Antennas, Spans (bridges), or Earth (cliffs)), and landing under a
parachute. While being an expert skydiver isn't an absolute
requirement, you need a great deal of experience in parachute packing,
canopy control, quick reflexes, and body position awareness before
this can be attempted with any real safety. Start with skydiving, and
then go from there. Furthermore, there are very few places where one
may BASE jump legally, as most locations are private property.
 
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