There was a single edge razor blade included with my makerbot to use for removing parts from the build platform. I do not like using a naked blade, and did not have a holder for it, so I made one.
First ensure that the top and bottom parts fit snugly together. I made them with a very tight fit, so you may need to file them a small amount to get things together. This is on purpose, to ensure nothing falls out of place.
Fit the blade into the bottom part, then clip the top part over the blade.