Chipboard or matboard (similar to the material cereal boxes are made of) are great materials for airbrush stencils.
Workflow
1. Use image trace to extract a cut line from any image2. Use pen tool to clean up lines and delete duplicates
3. For any floating features (see fish pupil) use shapes and to join - “shapebuilder” or “pathfinder” in illustrator
Laser settings
Matboard
90W laser
300mm/s
20% power