The first step is to download iso image. On the Linux Arch download page, you will find an ISO file that you can save to a bootable USB drive. You also have the option of burning the file to a blank DVD. Be sure to download the latest version and only download from the official website.
Then restart your computer and select the key in the BIOS as the boot drive. The path to the BIOS depends on the brand of your computer. In many cases, the key [F2] is however the correct one. If it doesn’t work, you can find the appropriate key or key combination in your PC’s user manual. In the BIOS, display the boot menu, select « Boot Arch Linux (x86_64) », save this change and then boot from the USB drive. You are now ready to install Arch.
