If you use the search box at the top of the page to find your printer, or via the drop down menus on the homepage, you can add a printer once on the printer page.
For Example
If you wanted to save this printer:Pixma MG-7750
As long as you are logged in there will be button at the top right hand corner of the product page that says 'SAVE TO MY PRINTERS'
If you click that button it will add said printer to the bar at the top of the page under 'Here are your saved printers'. You are able to add more than one printer, if you would like to remove a printer from your saved printers list simply click 'Manage Printers' and then click the small bin icon in the right corner of whichever printer it is you wish to remove.