I used 2 different types of string. For the thicker bracelet I used embroidery floss and for the thinner one I used friendship bracelet string- which you can find at walmart in the craft section. I keep both types of string on hand. Depending on the pattern some bracelets come out better with the thinner string- others are better with the thick string.
@Shiloh0805 I’m totally curious as to what kind of strings did you use to make one smaller/larger than the other? I can’t tell from the photo and I’m so curious.