If you want to ensure you have a consistent color theme throughout your presentation, you can select one of the Microsoft design/color themes, or you can create a custom color theme.
To create a custom color scheme:

1. On the Design tab, in the Themes group, click the arrow to the right of the Colors button
2. Select Create New Theme Colors at the bottom of the list
3. Change some of the theme color aspects for text and accents
4. Type a name in the Name field, to name your theme, then click Save
5. Note that the new color theme is now listed at the top of your color theme options

For more power point techniques see our PowerPoint Classes.