In order to achieve a specific goal in bodybuilding you will need to build a foundation for which to go about achieving this goal, and un-fortunately wether it is to cut fat or biuld mass, the highest priority, the leader if you like, is always going to be your diet.
You have to have a sound diet in place before you step into the gym if you expect to achieve something. Everyone knows this.
Lets be serious, this is a body"building" site, we all want to achieve something, so therefore diet is of the highest priority.