Obviously you have to get a design down on the body. I use a white or black china marker to sketch it out. then when I'm happy with the layout, I tape it with 3M fine line tape. I like the blue stuff. Filling in between is time consuming and tedious. I use 2 inch. After you tape it all off and mask back to prevent over spray, wash it down really good with wax and grease remover. Scuff all tape eges with great care. Make sure you get rid of all shiny surfaces. If the fine line comes up remask it. Wet or dry sand the rest with 400 or 500 depending on the kind of paint you're using. After you lay the paint down and depending on how elaborate the flame scheme is you pull the tape. This is the crutial step. You can pull the paint right off if you're not carefull. Get all the fill masking off first then work the fine line. When we worked with lacquer we sometimes pulled the fine line tape immediately before the paint was dry. Today you have mostly enamel and your better off letting it dry or harden first. Pull your fine line off at a 30 degree angle into the fresh paint, so that it cuts a clean edge. That's one of the tricks so you don't pull off your new flames. I hope this is helpful.