Although its more common on drums. Copy a drum track, apply compression to taste and blend. Thats it basically. I use the A-Designs Nail for this as well. Killer on punchy music!
Parallel Drum Compression - PUREMIX
These videos are absolutley excellent! The full versions are well worth the investment. The majority here should check them all out. Fab is an excellent engineer.
Here is another thread about this: http://recording.org/pro-recording-f...explained.html
FL rocks by the way. Not the best DAW but what it does, it does well.