Hi....my method is to use a length of string ...a knot tied at the correct length.....then use a straight pin to attach this string at the beginning of the woven towel. As the weaving progresses you simply use the string to check length...when you reach the correct length, use a brightly colored yarn to mark the end of one towel and the beginning of a new one. Reattach the marking string to the beginning of the 2nd towel...on and on...really simple.