Oreig (weaving) does not appear to be a permitted melacha on Yom Tov. Braiding is oreig - may one braid challos on Yom Tov? If so, would it follow that one may braid anything on Yom Tov so long as it is for Yom Tov?
From Rabbi Torczyner:
• May I braid challah on Yom Tov?
This is actually more complex than it may sound. On the one hand, acts from kneading and onward in the bread-making process are permitted on Yom Tov. On the other hand, the reason we don't braid dough is because it is "construction", and construction is prohibited on Yom Tov. Indeed, Rav Shlomo Zalman Auerbach is cited in Shemiras Shabbos k'Hilchasah, Chapter 11 foonote 43 as opposing the practice, although he does offer a potential halachic justification.