If you have a Mac with two monitors and you want to change the side of the second monitor, there are a few things you need to do. First, you need to go to System Preferences and then click on Displays. Once you are in Displays, you need to click on the Arrangement tab. In the Arrangement tab, you will see a picture of your two monitors and a white bar in between them. The white bar represents the space between your two monitors. To change the side of the second monitor, you need to click on the white bar and drag it to the other side. Once you have done that, you need to click on the Apply button and then the OK button. Your second monitor should now be on the other side.