I often use lacing strings in my class for art projects and lacing boards. When I need new ones, I cut pieces of yarn to the desired length and dip them all at one time into melted wax. After they've hardened, I break them apart and they all have stiff ends to start lacing. A fast way to cut several pieces of yarn or string at the same time is to find something in the room that is the right size to wrap the yarn around and then cut all the yarn at one time. Yarn wrapped around the back of a chair is just the right size for making necklaces.