Start with the computer powered off.How ?
Thank youStart with the computer powered off.
Insert your USB installer.
Power on the computer and press your boot menu key - Usually F12 but YMMV.
At the boot menu screen select your USB flash drive as the boot device and boot.
At the Clover menu screen select your hard drive and boot.
When you get to the desktop run the Clover installer and install the required selections to your hard drive.