My cat got into a fight with a stray and her ear is all messed up - how can I clean it?

Asked by troubleinharlem (7991) September 17th, 2010 from iPhone

I let her outside (she doesn’t go off the property because she doesn’t like cars, thank goodness) and I noticed later that she had a scabby ear. How can I clean it so that it doesn’t get worse? Should I take the scab off and clean it with alcohol, or something?

I’ll put up a picture of her if it would help, also.