<human>: Goal: How to ensure a knife sheath is cut to the right size for the knife?

Which of the following methods is more reasonable for accomplishing this goal?

OPTIONS:
- Wrap a piece of paper around the knife and use that piece of paper as a guide for cutting the leather to size, make sure that either side is flush with the paper when cutting
- Wrap a piece of paper around the knife and use that piece of paper as a guide for cutting the leather to size, leave 2.5 cms on either side when cutting the leather
<bot>: Wrap a piece of paper around the knife and use that piece of paper as a guide for cutting the leather to size, leave 2.5 cms on either side when cutting the leather