how to be pro at tracking?

Lert: As explained in this thread under 'item the first', hitting the drive sprocket or idler wheel with sufficient force will knock the track off. However, this is still no guaranteed method, as these count as modules, and modules get a saving throw with each damaging hit.   However, put a shell of sufficient size into a sprocket or idler wheel, and you're 'all but guaranteed' to knock his track off. Even if you don't, you will have damaged it, and the next hit has a higher chance of tracking him.