The GAM Cheat Sheet gives a summary of commands for the GAM tool that allows management of G Suite domains. It was created to put on the wall next to my computer so that I could quickly find the format of commands without having to look up the full docs.
GAM comes with the file GamCommands.txt that has the full command line syntax in BNF format for those who need more details. The GAM Wiki has user level documentation including setup and tutorials (it includes examples of how to use most commands).
The current version is v1.6.3 (20 August 2020) for GAM version 5.11.
If you want a black and white version to reduce the amount of ink required when printing, choose the "B&W" link next to the appropriate version.