Some tools let you adjust the look and feel of the participant session. Beyond setting the language and supporting text (discussed earlier), you may also be able to specify:
- The logo displayed before/after/during the test
If you running this study for a client, be sure to get an approved logo from them. - The color(s) used for backgrounds and such
Again, it’s good to pick actual brand colors if you can, while making sure the resulting UI has enough contrast for visually challenged participants.
If you’re using brand elements like logos and colors, be sure to include the organization's “brand” people (usually the Marketing department) in your pilot testing. We’ve worked with some companies that are very protective of their brand, and will read you the riot act if you deviate even slightly from their guidelines. Don’t say we didn’t warn you. 
Next: Providing a support contact