i use my straight baller powers over the prismas haha.
naw you just gotta lay down each layer of color
then go back from dark to light
and on the edge of each section go over with the darker one then while its still wet hit it up with the lighter one. i find that i get kind of a band of darker colors near the fade area so i just basically redo the whole fill.
idk if that makes any sense but yah.