(Important-Please do not take what they say personally, what they say reflects to their own self esteem)
Depending on your confidence you may or may not respond. Highly advised that you ignore and let them drown in their own low self esteem.
Guy 1: Yo, you are ugly and your clothes look stupid
Guy1: Whatever man, im still better than you
Guy1: (sigh...he wont respond D:) iight whatever man im out!!!
guy 2: Pathetic ~_~ SMH *pity*