Almost everyone universally wears jeans, so a simple blouse that is classic would be non-noticable (unless you are wearing 3 sizes too small!) or a golf button down type shirt if you are a guy. Most Americans wears tshirts that have statements on then which are give aways.
Mainly I was referring to the fact that an Italian woman never leaves the house unless dressed to the nines even if it’s just for milk and eggs while the young American woman is perfectly happy in a hoodie and jeans. It’s. Cultural.