How does it work?
Pick the circuit below what you project at. Go around and climb every boulder in that lower color circuit BUT you only have one try per boulder. No second attempts. The goal is to make every attempt as best as it can be to flash each climb in that circuit. Rest as much is as needed.
How does it improve your climbing?
This both gets you practice on all the technical needs that color circuit offers as well as works on your mental execution to get it in one try. Only having one attempt, you have to practice on your planning, focus, and putting in the best attempt you can.