From the Site Center:
- Click the Pages tab if it is not already selected.
- Select the Home page by clicking on its title in the site map.
- Click the Edit button.
- In the left column of the page for editing the homepage, click Colors.
- Scroll down until you find your desired color palette and click the name of that palette. You may change colors as often as you like.
- Use the Preview button at the top right of the page to get a better view of how the site will look with the selected color palette.
- Click the Save and Exit button when satisfied with your choice.
The two color swatches for each palette indicate the colors of the header and footer.