the way most park crews do little jumps. is they get plywood boards and a bunch of 5 ft or larger stakes. they set up the boards on the back left and right sides of the jump to the width and length they want. they stick the stakes in the ground behind the boards to support the plywood, they just start throwing snow on the back board let it accumulate then start adding some in the front for the transition then carve it out (if you have cold temps and fluffy snow ur going to need about 3x the amount of snow than jump size, just keep packing it down (the boards allow for the snow to stay very strong without moving. also after your done take the boards off and spray water on the back and sides maybe even the surface (best way is to get water just above freezing or atleast as cold as possible drink some but dont swallow, then spray it out of your mouth, keep your lips tight so it mists other wise it will be just a stream of water and melt the jump) good luck nig