One of the greatest aspects of Cinnamon is how customizable it is. Nearly every aspect of the environment can be changed, including (but not limited to) the colors of applications, desktop wallpaper, and even the theme of the Cinnamon interface itself.
To start customizing your environment, use the following steps:
Open System Settings and locate the Themes section in the first row.
A new menu will appear with three tabs: Installed, Get More Online, and Other Settings.
The Installed tab shows which Cinnamon themes are currently installed. If you've never customized themes before, you'll only have the two default themes listed (the following two screenshots). There is a green check mark next to the currently active theme.
Feel free to switch to the Cinnamon theme to see the changes right away. The colors of the panel as well as the application menu will change. Make note of the fact that the color of application windows (such as Nemo) did not change.
In the next tab, Get more online...