To change the close, minimize, and enlarge button or changing your highlight color is simple. First click on finder, then to applications folder, then to system preferences. When you are in system preferences click on general. Next to appearance click on the word blue and then in the pop up window change it to graphite. Changing this setting will make your close, minimize, and enlarge button turn a graphite color, also this will change check boxes and circle bubbles to a graphite color too. To change your highlight color click on highlight color and in the pop up window select a color you would like to use, then go to Google and try to highlight something, you will notice that the color has changed to your selected color. View the video below for further instructions and for help.