Themes are a set of colors, fonts, and a logo to use in multiple places to make the project consistent for any callouts, arrows, shapes, and other assets.
To manage a theme, select File > Manage Themes… (PC) or Camtasia > Manage Themes (Mac) and in the dialog box that appears. You can:
View and edit existing themes
Rename or delete themes
Create new themes:
Give theme a name.
On the Color tab, change the five colors and select an Annotation Background Accent color.
On the Font tab, select two fonts.
On the Logo tab, browser to and select a logo.
Once you create a theme you can APPLY it to an annotation to change the color/font of that annotation by selecting it from the theme drop-down menu in the Properties panel. This is a big timesaver because you don't have to change the color of the annotation in the Properties panel.
Use the preview pane to see how a theme will look in your project, and click on the black and white color to see how it looks against another background.
You can also select a Theme and change the color of a font.