NOTE: This is a more advanced concept. If you don’t know yet what a Slide Master is, or how to create one, click HERE.
If you have a presentation with hundreds of slides, one look for all the slides may not do the trick. In this case you’ll want to use more than one Slide Master, and therefore have more than one look.
Click View / Slide Master.
You should already see one created with all the attendant layout suggestions.
Click Insert Slide Master.
A new Slide Master will appear beneath the old one.
Edit and design it to your specifications.
Staying on the Slide Master ribbon, go to the ‘Edit Theme’ group, and click the Themes icon.
Click ‘Save Current Theme’. (By the way, this is where I got initially confused. When you save a theme, you are actually saving the look of a Slide Master. Two different names for the same thing.)
Save it to it’s default location, or wherever you can easily access it.
Close the Master View.
You are back in your presentation with several slides.
In the Slides panel, select Slide #1, or multiple slides.
Click on the Design tab. (This is where I initially got confused even further. Design is just another word for Theme, which is just another word for Slide Master. Feel free to correct me if I’m wrong on this, but it’s the only way I can understand it. For the purposes of this tutorial, just think ‘Slide Master = Theme = Design’.)
Locate your recently created Slide Master(s).
If you simply click on any choice in the design tab, it will affect every single slide. We don’t want this.
We want multiple looks for multiple slides. So do NOT simply click on your choice in the Design tab, but instead, RIGHT CLICK.
The obvious choice from there is: Apply to Selected Slides.