Ok there’s a few things I recommend you decide on before adding a class to the schedule.
Decide if it is a lecture or follow along tutorial. If tutorial make a zip of any relevant files and make it possible to share them (thumb drive, dropbox, anything)
Decide the main subject and leave time for questions.
If someone says they do it differently, learn how they do it and let em know there are several ways in photoshop to do the same thing. Pearhaps mention why you do it this way. 
Decide how long the class will be
Pick a day and time where you can get a decent turn out.
Get in a half hour early because you may need to rearrange the room and set up your laptop to a TV or the projector. (if you don’t know how to do this practice this a few days before the class so you know how to do it)
When scheduling a class if you choose to get an honorarium please send the extra amount to Creative Arts.
For creating a class there has been a new system created. You’ll find good info on how to submit the class here. New Calendar and Honorarium process
My recommendation. Check the calendar to see if there is or not a class already taking place in the room and time you want. If so, you will need to choose a different room or time. I recommend the Purple or Interactive class rooms for tutorials that the class will follow you in. But if you want to just talk, either of those and the lecture hall would work.
https://dallasmakerspace.org/calendar/
You create a class by going to this site and clicking on “Add Event”