I tend to have a single style I keep to with my usual outfit which - amusingly - is the bedhead style! .. Which means I never really have to redo my hairdo if I stop playing for a while, I suppose. ;D
I haven't changed my Mayor's hair since her first haircut in July 2013. I really like the colour and style (dark blue, with the medium length formal/vintage female hair-do) and can't imagine my Mayor with any other hair now! ^_^
I change it when I switch outfits and get tired of the same thing, usually.
But lately I've been taking long breaks from the game so I've just been leaving all of my characters with bedhead because I can't be bothered to keep changing it. I like bedhead as well so it doesn't really bother me.
i change it once in a while, if i get sick of looking at it. for a long time my hair was the pink pigtails, atm it's the same hair style but a different color (the honey brown kind of color)
Usually I don't change mine. Sometimes I randomly change the color from pink to blue or vice versa. It really just depends.
I found someone online that liked to visit my town and whenever she came over we changed our hair dos together. It was fun.
For my first mayor:
I usually stay between 2 hairstyles.
1. The pigtails
or
2. The straight down hair.
And like I said earlier for color it's either=
A.Sky Blue
or
B. That light pink that I can't remember the name of.
For my current/2nd mayor:
She is based off The Little Mermaid character Ariel so I try to keep her hair based off that. So usually it's red with the longest hair style possible, or pig tails.