Advice of steps involved to change ink cartridge

Access the manufacturer's web-site:

http://www.usa.canon.com/consumer/controller?act=ModelInfoAct&tabact=DownloadDetailTabAct&fcategoryid=334&modelid=11865

Select "MP450 User's Guide".

Download this PDF file.

Scroll to page 76, Chapter 10, Routine Maintenance.

Follow the instructions, step by step.

The Canon Pixma MP450 uses four-color ink: one black tank and one tricolor tank (it ships with the high-capacity tanks). You can access the tanks by lifting up on the control panel; a plastic support bar flips down to support the lid, much like a piano lid or a car hood. The tanks are a cinch to replace. The high-capacity black tank costs $29.99 and the high-capacity tricolor tank costs $34.99.