Diet Diet Diet! and Exercise.

This has been something I really tried with to begin with and to be honest it is easier and harder for certain body types.

Essentially, exercise and careful eating will get you the most of the way, for me I can get down to 15% by being careful and going for a good weights and High Intensity Interval Training Session.

If you want to get the lean 8-12% look you need to really reduce the amount of fat and complex Carbs that you consume.

There is a diet called the slow-carb diet that is good for this (google it) where essentially you eat complex carbs and protein. I started to get on well with this but then fancied a pizza hut..

Essentially eat lots of cereals, beans, eggs and vegetables, eat meat that have lower fat such as beef and chicken brea fillets (no skin) and grill them to reduce the fat more.
Remove the bread and bread items (and even pasta to be really effective) from your diet to make sure you're really getting lean.