The most important thing is not to overtrain and leave a substantial (about 72 hours) amount of time in between training a muscle so it has time to heal.
This is my work out:
Monday: Chest + Triceps
Tuesday: Legs
Wednesday: Off
Thursday: Shoulders
Friday: Back + Biceps
Weekend: Off
This allows you to work the heck out of your muscles, have them exhausted and have the fibres nice and ripped, and then allows you to repair them while working out using other body parts the next day.