Did you read my earlier post on auditing an AdWords account? If not, I encourage you to start there for a foundation, especially if you have never audited an AdWords account.
In that post, I talk about checking your budget, reviewing your campaign structure, checking the number of ad groups, and ensuring your ads have a CTA, among other things.
Once you’ve read that, you are ready for Part II. My full post is available at Supermetrics.com