To enlarge text and images on the site:
On a PC:
Hold down the 'Ctrl' key and press '+' to enlarge.
Hold down the 'Ctrl' key and press '-' to reduce.
To reset hold down 'Ctrl' and press '0'.
On an Apple Macintosh computer hold the 'Cmd' (Apple) key instead of 'Ctrl'.
The BBC also has information on how to customise your computer, and your browser, to make them more accessible in their 'My web my way' section.