What should I wear to a job interview for a home decoration store?

I have an interview tomorrow, and I'm pretty unsure of what to wear. It's for a general sales position at shop that sells candles, fake flowers, ornaments and stuff like that. The girl who was working there looked pretty casual, but does that mean I should turn up casual? I want to look smart but not like I'm going for a business executive position... Any ideas? Oh, and I'm female.