Hairband is crafted with Tailoring in Mabinogi (hat). This page lists everything needed to make it, checked against the game as it exists today. The interactive planner lives in the Tailoring Companion.
How to get the sewing pattern
The sewing pattern is rank F and survives 30 uses; every crafting attempt spends one use.
Walter: Buy it from Walter's General Shop in Dunbarton. (400 gold). No special requirements, just gold.
Effie: Buy tailoring manuals directly from Effie's shop at Qilla Base Camp in Port Qilla (400 gold). Standard gold purchase, no special currency needed
Galvin: Buy a pattern from Galvin's shop under the Observatory in Emain Macha. (400 gold). None beyond having enough gold.
Granites: Buy a pattern from Granites's general store in southwest Filia. (400 gold). Elf-allied humans get a discount, other races pay full price.
Pierrick: Buy it from Pierrick at the general store in Taillteann. (400 gold). Prices drop five percent on Wednesdays from the weekly shop discount.
Ilsa: Buy a pattern from Ilsa's general store in Tara. (400 gold). None beyond having enough gold.
Exploration: Use L-Rod Exploration or Land Maker across Iria to uncover hidden treasure chests.. Requires an L-Rod or Land Maker tool equipped to search.
Neid: Defeat Neid, the field boss that lives in Lake Neagh inside Abb Neagh.. Fought in the open field, no special pass needed, but it hits hard and works best with a group.
Sources that no longer exist: Production Gachapon.
Materials
Expect about 1 attempt per finished item (99.9% average progress per attempt). Per-attempt materials are consumed on every attempt; finishing materials once per item.
Each attempt uses
1× Cheap Fabric — Buy directly from any general goods NPC shop.
Finishing (once per item)
1× Cheap Finishing Thread — Buy directly from any general goods NPC shop.