Move your mouse/finger around. Experiment with the toggles by clicking on them. When you want to toggle the first one off, it will prompt you with a notification (If you want one go to my profile; you can find it under "shared projects"). Choose "freeze" to freeze the color that it is currently on while changing, or "red" to switch to a classic red laser. The "small/big" toggle has three options: Big, medium, and small. Click on it to change the size of your laser. You can click space to show/hide the toggles.
This happened when I was experimenting with pen. Like @papipupepappa said, learning by doing is best. :) It's a bit jerky, let me know if you have any suggestions on how to make it smoother. --------------------------------------------------------------------------- - Shared 5.13.2021