Not sure about paint patterns, but Jedifather gave me a tried and true method to painting resin.
1) wash it with a little dawn and warm water.
2) go over the whole thing with sandpaper to break the surface a little
3) fill any tiny holes with super glue (maybe dust some baking soda in the glue, I've heard this works) or Apoxie sculpt for larger filler areas.
4) 80-100 grit sandpaper the whole thing, then use a medium like 200 and then a 600 or 800 to smooth everything out.
5) rinse it again lightly, and maybe even use some alcohol or nail polish remover to remove oils from your hands.
6) Now you're ready, I've had great results with the rustoleum 2x consumer rattle cans "that also bond to plastic!" Dust some paint on from an arm length away, wait like 5 minutes and go back and dust again. Repeat until coated. You can use a heat gun LIGHTLY to help cure it, don't want to melt the damn thing haha