I learned how to make transparent backgrounds/objects more or less transparent.
I have not questions at the moment. I think I need to just play around with it.

Tell people in some detail what you are doing. Slides should help but not be self explanatory requiring nothing from you. Avoid words such as like, so, um, stuff, etc. Do not talk about things that do not matter to your presentation. Look at the audience, not at the slides. Do not read from the slides. Do not tell about your weaknesses (this is really bad but I included it anyway). Avoid slang. Have all slides matter!