To set the boot order of your computer you will first need to gain access to your computers BIOS.

To do this, simply press Del, Insert or F2 as soon as you power on the computer. Each computer will require you to press a different key but these three are the most common. On some computers you will need to keep tapping the appropriate key.

Note: Keep an eye on the information that is on screen once the computer is booting. You should see something along the lines of 'Press XX to enter setup'. XX being the key you need to press to enter the BIOS.

Once you have gained access to your computers BIOS you will need to look for a section titled 'Boot devices' or 'Boot order'. Change the order of this list so that your CD/DVD drive is listed before your computers hard drive. Once you have this changed, save your new settings (which is normally done by pressing F10) and exit the BIOS.

Your computer should now be able to boot from a disc at start up.

Note: Sometimes you may need to tap F11 during the boot sequence to gain access to the boot menu, which in turn will allow you to boot from your desired disc.