Break it down into simple sections:

   *  Gates and First Straights

   *  Cornering and Passing

   *  Jumps

   *  Rythm Sections

   *  Attitude

Each and every track needs to be broken down into small chunks and them worked on many times until each part is pieced together bit by bit into a complete lap.

The single most important lesson about BMX is to get as much track time as possible, in essence any track will do. but practise time before an event can change you from being mot'ed to a B final, or from a B finalist to an A finalist, then from 5th to 1st.

Check out a track one to two weeks before a national.  Anyone who is serious about doing their best will be there to get as many gates and as much track time as possible, you can make a long list of who is there - many will be from other regions getting in hours of practise.  Another thing, watching many top, experienced riders, you will find them practising from one berm to the next working on a single straight and lines and jumps to perfect them.  After they are happay with each section of track they will move on to the next straight, manualling, jumping and pumping through the jumps.