Add a little light brown or wood coloring to the ties.
Finally, add the coloring to the forward part of the train engine or cattle guard. Now the rest is up to you. You can turn everything other than the train and track into a transparancy then place your illustration on any kind of background you want.
Drawing and illustrating can be both fun and rewarding. The more you do, the more often you practice the various artistic techniques you've learned here, the better artist you will become.
Remember, in order to get better at art, you need to not only practice your skills but challange yourself with more and more difficult artistic projects.