At your local hobby/arts crafts store should have a section with acrylic/enamel felt tip pens for drawing or painting. I use a fine tip water base acrylic paint pen to do my raised lettering in white. Most times I get a one coat coverage with little or no bleed over the raised letter. If I do, a trip to the sink or wet paper towel to wipe off and try, try again.
If an acrylic ink pen is unavailable you should be able to find any small bottle or jar of white/yellow acrylic water based paint. Use a toothpick, I usually sharpened mine to a finer point (before I started using the pen), dab a little onto the toothpick and go to lettering.
Acrylic water based paint will work better the enamel or other. With enamel or other the paint will react with the rubber tire and never dry/cure leaving the possibility of smearing/smudging and making a general mess. The acrylic will dry shortly after application and then you can "paint" the tire sidewall with a acrylic (water base) flat clear to tone down the tire/letter shine. It's worked for me and I hope this helps....Chuck
The track is actually a remnant of a old TV stand the was up in my garage. The stand width is about 48" long and 16" wide and basically pressboard. I used some dark/med grey stone textured spray for the rough surface. Use some flat black to mist a couple of coats or give an uneven coloration in different areas to resemble asphalt fade. I taped off and spray flat white for the lane stripes and used a 2" x 3/4" strip for the retaining wall.
I painted the wall white, added some tire scuffing by taking a tire mounted on a backing rim with a metal axle, smearing it in some flat black paint and rotating the wheel assembly down the retaining wall. Apply heavy for initial tire contact to light/fade upon coming off from sideswiping the wall. Plan to add either track name or add some color scrapes in addition to some background billboards. Also to give the effect of different sections of the track, paint the backside of the retaining wall, either leaving clean or adding different enhancements to simulate different points/areas of racing around the track........hope that helps! Chuck