There are two steps during tiller, long string and short string. For the long string I use parachute cord with two leather boots, it's adjustable, you want the string just slack enough to make it easy to put on the tips. You don't want the string too long, it will mislead you in the process. When it comes to short string, I cut temporary knocks and I made a long flemish string with a loop at one end and use a timber hitch at the other, like Russell does . I won't make a good string for the bow till it's done.