That's countersignalling. It only works when you're so accepted that you can get away with bad signals.

Signaling is almost completely context-dependent. What is countersignaling and what are "bad" signals is a function of who is signaling to whom.

You mentioned "the value of dressing like other people" -- in some situations it might be positive, in some situations it might be negative. There is no universal rule.

In general, the formulation of the question is too crude. Most clueful people try to be unique and interesting without being weird. That's not necessarily an easy balance to strike. Talk to a (socially competent, non-teenager) girl :-) They have a much better understanding of these things :-D