Depends on which ones you have Jim, the all metal tracks of the ones with rubber blocks.
Here's the procedures that I use.
Rubber Block Tracks -
1. base coat of flat black
2. for the end connectors and guide horns I brush paint them with gunmetal
3. dry brush the end connectors and guide horns with rust
4. dry brush the end connectors and guide horns with steel
5. burnish the end connectors and guide horns with ground pencil lead
6. dust with pastels with the rest of the vehicle
All Steel Tracks
1. base coat of gunmetal
2. dry brush with rust
4. dry brush with steel
5. burnish with ground pencil lead
6. dust with pastels with the rest of the vehicle
Happy Modelling and God Bless
Robert