great topic and sound advice by softgrey 
basic rule for casting looks is simplicity.
models need to look like 'a plain canvas' in order the casting director
can actually see the potential, going to a casting in an '80's look might
turn fatal if the casting is for vintage editorial.. keep it simple.
jeans and any kind of non too obviously trendy tops are top choices
among models, they keep it fresh and 'natural' this also helps the model's
psychology during the casting, like almost famous and others hinted,
it is really important to feel at ease during castings.
i need to check on Ali
