You can tell if Xming is running if the Xming logo is displayed in your taskbar. If it is not already running, simply look up Xming in the Windows search bar and click Open (or hit Enter). It may not open a window in the Dock, you should see an icon of a white square containing a black X. (1) Start X11: go to the Applications folder, open the subfolder Utilities, and double-click on X11.app. The software you need is already installed on your Mac.