• Make sure Secure Boot is enabled.-Full Security is the default Secure Boot level. Before installing Windows, if you changed it to No Security, turn it back to Full Security. You can use any Secure Boot configuration after installing Windows without compromising your ability to start up from Windows.
• Create a Windows partition with Boot Camp Assistant.-Open Boot Camp Assistant from your Applications folder's Utilities folder. Follow the directions on the screen. If your Mac prompts you to insert a USB drive, connect your USB flash drive to it. It will be used by Boot Camp Assistant to generate a bootable USB disc for Windows installation.
• The Windows (BOOTCAMP) partition should be formatted.-Your Mac will restart to the Windows installer after Boot Camp Assistant completes. Select the BOOTCAMP partition and click Format if the installer asks where you want to install Windows.
• Windows should be installed.-During installation, unplug any external devices that aren't required. Then, to begin installing Windows, click Next and follow the onscreen instructions.
•  In Windows, run the Boot Camp installer.-Following the completion of the Windows installation, your Mac will boot into Windows and display a 'Welcome to the Boot Camp installer window. Install Boot Camp and Windows support software by following the on-screen instructions (drivers). When you're finished, you'll be asked to restart.

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