I see why the clerk said to snip the 'bridges' as someone called them. She meant once you do that, then you can follow the design left behind which is the same design as when left as one piece with the 'bridges. Her way, you just don't have as much template in the way. This is the same as some of the templates I have used in the past for painting and you have to remove the inner plastic to get to the outer design.
However, I think it would be better to leave together and use powdered chalk and 'pounce' it on the design, lift, move pattern to next spot, etc. or use a washable marker.
I guess it is one of those things you have to see used to understand.