We wears formal clothes
Business professional and Business casual
I was a labourer and dressed as one with work boots.
Wear an outfit that you would use when you go to an interview with a company, business-like.
In Adecco you have to wear a working boots.
I would wear the attire that would be appropriate for the position that I am applying for. If it is a general interview I would make it be at least business casual or business attire.