Canon 1100 Reference Manual page 111

2
Pull out Drawer 2 and remove all the loaded paper.
3
Squeeze the lever on the left guide as shown below. Without releasing the
lever, slide the left guide to align it with the mark for the desired paper size.
When adjusting the left guide for A3-size paper, slide it all the way to the left and then fold it over to the
right.
Left guide
3-7
Loading Paper
3