first make a foundation out of logs rocks anything you can find really and once done get some damp dirt and add to the foundation so you can shape the jump when you are finished soak it with water and leave it to go hard
dirt-biking is for dirt-bikes it can be either stunt or mud riding
a ball can't jump
Depends on you, your bike, your speed and the size of the jump. Weak bike + heavy rider + big jump + high speed will add risk to it while strong bike + light rider + small jump + low speed will make it fairly safe. You will probably be somewhere in between these extremes so there's no way of telling how "safe" you will be.
cruise until you get up to the jump and when you hit the very end of the jump gunn it
Yes you can all you need two do is separate the seat to make two seats
walk outside. Jump in dirt. It will put a dirty footprint on the bottom of your foot
i do. 7235 vertical feet
Marzocchi bomber forks are used as a dirt jump shock but i ride DH on my dirt jump bike with those shock and can manage.
not all are. if you want to do dirt jumping i recommend you do not use a normal mountain bike. get a proper dirt jump bike. i used a felt q520 xc bike to dirt jump and the forks broke and i took it in and the mechanic said i had damaged the frame and it was close to snapping.
big chunks of dirt or ice with tails
If it is part of a PE swimming class, yes.
Not as scary as landing on your face.