Tackling complex projects using photoresist takes skill at the design stage. You don’t want etching lines that cross over each other. In general, multi-stage sandcarved images are simple line art patterns without many open areas.
A good rule is blasting the same item several times until you develop what looks most desirable before producing the final piece, all while working backward because you can only truly appreciate multistage carve items looking through the glass surface.
—Liz Haas and Billy Willis, Rayzist