To change the color of the selected highlight, simply click on a different color from the palette under the color wheel. The color with the glowing highlight is the selected color. In the next window, look for the color wheel. In this example, the LED color is set to red, but it may be a different color on your computer. In the Logitech Gaming Software window, click the on the lighted, colored part of the mouse. Start > All Programs > Logitech > Logitech Gaming Software 8.x
To configure the LED colors and to switch between the color modes: For more help assigning buttons, please see answer 360023242334. NOTE: To change between colors and their assigned button sets, you must have one button assigned to Mode Switch (G300). Each color on your mouse can also be assigned a separate set of button assignments, which means you can have three different sets of button assignments in a single profile. You can configure up to three different colors for each profile. The G300 supports eight different lighting colors (seven lit colors and 'black', which is the LED turned off).