The auditing course recommended by slycamel is important however I would also recommend attending a course which covers the basic concepts of quality systems. A number of organistions offering aviation courses also provide 1 or 2 day courses that cover this subject
I would also suggest researching and becoming familiar with safety management systems as these are integrated with company quality systems and come into effect in the UK from January 2009 for Part 145 and Part M organisations. The following CAA link provides useful info on this.
Safety Management Systems | Operations & Airworthiness | Safety Regulation