There is no mystery to developing the best abdominals that your genes will allow you.  It will take some know how, and some good old fashion hard work amd effort.  One of the key componets to getting those abs is in the way you eat.   Your eating habits will have to be right on if you expect any real results.  Try eating veggies that can burn belly fat.  Along with your cardio make sure to pick the ab exercises that work the best for where you are in your fitness progress.  You may need to get creative if you are more advanced than a beginner.