@mirage with most patterns I use strings as long as from my fingertips to the middle of my chest or opposite shoulder (about 30-40 inches/ 80-100 cm each). If you double check the path of each string in the pattern, you can see some strings will use more knots and might need to be longer, and other strings (like both end A strings here) don't have any knots if used for the straight-edge technique (as long as you keep them to the outside edges) and can be fairly short. 👍