You could start at it with scissors to give it a general shape, then use sandpaper to give it a worn look.
facebook page // nh/mass cosplay events
Next event: Summer Matsuri
COSPLAYS IN PROGRESS
Umbreon (Pokemon gijinka) - Constructing
Gaius (Fire Emblem: Awakening) - Buying stuff
Vaati (LoZ Minish Cap) - Planning
Soren (Fire Emblem: Radiant Dawn) - Constructing