Blue Laser Refresher Material


I took the class on the blue laser awhile ago but never got the chance to try out any projects. Is there a location where I can find refresher material on the laser? I was able to try a test run on my acrylic (0.25" thick) but I was having a hard time dialing in the settings to give me a similar output to the class. I have a picture from the class of the settings I used as a starting point. Do I need to test the focus of the laser, if so how do I do this?