There are a few things you can do to cut out a part of a letter in Illustrator. The first is to use the selection tool, which is located at the bottom of the tool palette. This will select all of the pixels in the area you want to cut out. Next, use the arrow keys to move the selection around until you have a clean area that you can work with. Finally, use the command key (or your mouse) to make the selection disappear and start cutting out your letter.
