I'm not familiar with the stamp but it sounds like Nanette has given you the way to get a sinlge image (just don't ink up the part you don't want to stamp). When you do this, don't foget to peel away your tape once you've inked up and before you stamp (sounds obvious but ask me how I know
To stamp more than one image and have them overlapping, you might want to explore masking. This is a really simple technique but it still makes me grin like a giddy child every time I do it. There's a tutorial for basic masking on this site here
. The key to success is to use something thin to make your mask (Post It notes are ideal) and to cut just inside the stamped line rather than on it or just outside.