How do you clean a canvas and wool Carhartt coat?

I have a Men's Carhartt coat...wool interior, and canvas/corduroy exterior. The labels are so worn that the cleaning instructions are not on them anymore....help? I'm just beginning to learn to be a housewife :/ so I don't know everything about cleaning. How can I wash this at home with out damaging it. It's a work coat, and has taken a beating and really needs to be cleaned. Help?