I need brown dyes, where can I find it or buy it when it's not in the shops?
Comment found on Love Nikki-Dress UP Queen: Brown dye
Go to the Recipe Workshop and choose "Customization". In order to customize, you need a item that can be customized (not all items can be customized), dyes or patterns that can be purchased in the Arena Exchange or the Association Shop, and Material that can be gained by decomposing unneeded clothes. This is a feature that is UNLOCKED early in the game, but if you do not have this feature, keep playing to unlock it.
Comment found on Love Nikki-Dress UP Queen: How do u customize items
LOL I think my comment above explains it, but you exchange starlight coins you earned in the arena competition for things like coloured dyes, recipes, and materials (so crafting/customization stuff only).
Comment found on Love Nikki-Dress UP Queen: What is arena exchange ? ...