Replying to Bomb drop

ight so my friend and i found this 15-20 foot tree for that is perfect to bomb drop.... the landing below is slightly down hill so it wont be that hard to make a landing so we dont fuck up our backs/legs. I've done cliffs this size but never bomb dropped something this size. If it is aroudn 15-20 feet tall and the landing is already slightly down hill what should i add for a landing? i obvisouly need to add a bunch of snow but how high should the snow pile be and at what angle shold the landing be and should i powder it up? I'm new to lease and dont wanna fuck my back up so help would be great....