I look terrible in buffs! They accentuate the crease between my eyes that would be obliterated by Botox, but I refuse to go there (so far). I just look angry in a buff. I have to have bangs to hide the crease and look like the (normally) happy person I am! 
But in answer to the original question, I often carry a ballcap in my rack bag when I take utility rides, and I take the helmet off and put the ballcap on to go into stores. The brim helps hide the forehead crease (check my avatar: bonus points if you can find a forehead crease!)
When I used to do club rides, I would keep the helmet on because I am the queen of bad helmet hair and sweat like a pig.
Emily
2011 Jamis Dakar XC "Toto" - Selle Italia Ldy Gel Flow
2007 Trek Pilot 5.0 WSD "Gloria" - Selle Italia Diva Gel Flow
2004 Bike Friday Petite Pocket Crusoe - Selle Italia Diva Gel Flow