The excess strap material that hangs from one's watch buckle can look extremely awkward and unprofessional, but more than anything, it can be very annoying to the wearer. While some leather and cloth watch straps can be difficult to modify, a rubber one is pretty easy to cut down. If done correctly, nobody will ever notice that you did it yourself.
How to Cut a Rubber Watch Strap
Wrap the watch around your wrist, and push the strap closest to your body under the bottom part of your wrist. Slide it through the buckle on the far strap, and place the buckle post into the notch that feels comfortable but securely fastens the watch band around your wrist.
Measure the strap from the end of the excess part of the strap to where it meets the buckle. Take note of this measurement, and subtract a half inch.
Place the watch face up on a level cutting board and extend both of its straps out across the surface. Place the beginning of the tape measure at the end of the lower part of the strap and extend it upward, across the strap, until you have reached the measurement in the previous step.
Position the tape measure on either side of the lower watch strap. Extend the tape across the lower strap so that the top width end is flush with the appropriate measurement on the tape measure.
Apply pressure on the ruler with one hand to firmly secure the strap from moving. Cut the rubber strap with a razor knife using the other hand, while carefully following the straight width end of the ruler.
The amount of rubber you wish to cut from the strap is up to you. Leaving about a half inch of excess strap seems to look the nicest, and it is not enough extra strap to cause a nuisance and discomfort.