I shower every other day (or every other two days, like if I shower on Monday, I'll shower again on Thursday), usually before I leave to go somewhere (usually work). It really depends on how much I feel I need a shower. I wash my hair every single day, though.
My showers usually last around 10-15 minutes. I wash my hair when I get in, then my hair again, then my body, then my hair, then my face and then I get out and dry off and get dressed then go out of the bathroom until my hair dries (while drying my hair with a towel) and then I come back to style my hair when my hair is dry.