well i would say to wait a while, and let yourself start to get over the break-up and move on. I have a mate, who when she broke up with her boyf, started dating someone else immediatly and shanged everything. I think that change is good, but wait for a while before changeing everything, as otherwise you may, as my mate did, end up wearing colours and styles that you as yourself dont nessacerily like but suit your mood of being upset.
My mate has made comments of going back to wearing colour(she wears mainly blue(dark), Dark Green and black,generally low, down colours right now) as she feels that at times she is ok till she gets dressed and the colours remind her of the breakup and rebound relationship and how low she felt, and starts feeling low again.