This system for charting music has been one of the most valuable skills I've learned for my professional music career. It's helped me prepare for gigs that I could NEVER have done without it and has helped me prepare for crazy gigs where I needed to learn 40 songs in 2 days (a few times). Having an effective charting system also saves you time prepping for gigs as well as helps you learn music deeper because you are combining two senses (hearing and visual).
To download the charts seen here, a list of all the tech used, and chart templates for your computer - download now for free:
https://www.timbuellmusic.com/learn-in-one-listen