Paint the plywood. For best results you should pre-paint the plywood but if you'd rather paint it after you can do that as well. You will need Red, Black, White and Gold painted pieces to match my example. 

Cut the base from 6mm wood. No need to paint.

Cut and engrave the Red and White pieces, and cut the Black and Gold. The engraving on the Red and White is used for alignment since the letters and thin black border pieces are difficult to align properly without them. 

Use a good wood glue to glue the Red, White and black numbers to the base piece. Make sure to clamp it or put something heavy on top to ensure it dries flat.

Glue on the letters and the black border. I used Gorilla superglue for this step but any glue should work. Wood glue tends to dry yellow/tan so if any seeps out it will be visible on the front of the piece though.