Custom print size iP110

Hello.

I use a Canon iP110. I need to print to a custom card stock size of 6.5 X 10 inches. I do not see a way to set custom paper sizes when I go to print. All that appear to be available are the standard 8.5 X 11; 5 X 7; 4 X 6 etc. How can I set it up for 6.5 X 10?

Thanks in advance for your help.

Hullersgill