This is a little trick I picked up from Don Asbee, my blacksmithing mentor.
Step 1: This Tape Is Ready for Retirement
Step 2: Snippers and a Marker Are the Only Tools You'll Need
I've cut out the entire roll out of the housing using snippers.
Do not cut the first foot or the end off of the tape until you have all the tape cut out of the housing. If the end is cut and the tape is released into the housing you will have to take the housing apart to get the tape back into your hands again.
The heroic first foot will be retired.
Step 3: Try to Snip Precisely Through the Center Black Line Every Foot.
The beginning of each foot is the most important edge, so orient your cut in the snippers so that you can see each start of every foot.
Whoops, looks like I missed the center of the line by a hair on the top.
Step 4: Be Carful, If You Don't Cut Straight You Could End Up With a Sharp Burr and the Corners Are Razor Sharp
I've pulled the burr down so that it can be seen. The corner are super sharp, if you don't trim a small radius you will eventually get sliced.
Step 5: I Prefer to Block Out the Distracting Numbers With Black Marker
Take your time. If you screw it up, rubbing alcohol can be used to wipe away the ink.
Warning! The corners/ends are sharp (even with rounded corners) so keep away from children if your doing this at home. Don't ask me how I know that this can be a problem.
Now give some away to your friends and stash the rest of them all over you shop. They stick to tiny magnets too so you can keep them in convenient and clever places.