Heres a green craw pattern thats really easy and can be done with other colors as well
white base coat
dirty orange(red,10 drops yellow 6 drops and a few drops of black just to tint)
cut grass green
black
after the base coats dry
spray dirty orange all but the front of the belly,before drying blot with slight damp rag to take away some paint but not too much,dry with heat gun or blow dryer.
spray green lightly over bait it will turn the bait a molten green dry with heat gun /blow dryer
lay stencle on side of bait hit with black for the body segments then lightly along edges of segments,
dry as above turn bait on it back so you can see the white belly you left in the begining
with a peice of paper/plastic spray lines letting the black fade as you work down the belly from one line to the next
so it looks like the belly/tail of a crawdadwith the white showing thru