If you print from illy, you can actually tile your artwork from the "print" menu. When you click print, set your page dimension then in the "setup" tab, check "tile full page" you can also enter a value for overlap. Click done, don't print yet, go in the "view" menu and click "show page tiling". You will see how Illy tiles your image.
One other way would be to use a clipping mask the size of your print. I you try to divide path that have brushes or gradient, weird stuff is going to happen.