Prospective job candidates should dress nice and neat, but not too fancy. Many ReStores operate out of older warehouse buildings, so employees and volunteers will most likely wear jeans, safety shoes/boots and a company shirt. Unless you are applying for an office job, you probably shouldn't dress overly 'professional' for an interview... but at least try to appear presentable.
If you are applying for volunteer work nothing to special
Clean clothes, no rips or offensive t-shirts
Casual wear , nothing fancy
Wear what you feel comfortable in It`s is who you are not what you wear.