Depends on how new it is. Just put in the necessary amount of quarters if they're needed, then use the dials and/or buttons to get the machine to recognize what you want it to do. Like do a cold wash for colors or something.
Usually, there is a knob/button (on top of the washer) to push (button) or knob (pull) which will engage the washing machine. If it a top loader, put the detergent in first, before the clothes. Don't use hot water, only cold. Wash colored clothes and white clothes separately. Good Luck. Save the "pink" clothes for Easter. :)