Please show Mike. I have to figure out the lines. When I use the modeling masking
tape, it pulls up the paint. I can't free hand it. I have colored watercolor pencils and
they don't look right. I am going to have to "lighten" the road with either a wash of
gray or pastel chalks, gray and white.
Here are a couple examples...

The roadway is styrene and it was painted using Testor's Flat Dark Gray Aircraft Paint.
The cracks were made using a fine-point pencil and the tar-lines were made using a fine-point Sharpie.
The filled pot-holes– Well I just varied the color of the paint I was using to vary the age of the pot-hole was filled.

The roadway is bass-wood (I needed a roadway that could be lifted because I have staging tracks underneath) that was painted with Testor's Flat Light Aircraft paint.
This road shows much more rehab over the years (water-line breaks and such) with one area being patched over twice.
Also the lining on this road is all RC cars racing stripes... Don't remember the width but very, very narrow. My problem with using colored pencils is that you can not get the width of the lines as narrow as these stripes.
If you didn't pick up on it, I luv Testor's Aircraft gray's for simulating asphalt.