just some basic info
you need a drop in to get speed probably you want it about 7 ft. talllay down some astroturf, you can buy this at home depot, lowes etc. this will help you gain speedyou want to make your rail out of wood and screw in some pvc pipes at the top. the pvs pipes slide amazingly well.you probably want your rail to be about 10-12' long.and you want it to be around 2 feet tall-ish
just some basic info, hope i could help.