Select an area or item to place the inlay on. Measure the area for the inlay, from top to bottom and side to side to give you a reference for the size limits of the inlay. Create or select a simple line drawing image at the full size of the inlay. Draw or print it out on paper. Divide the drawing into clear, easy-to-define sections, much like a color book or paint-by-number. Make a copy of the image.
Select wood grain colors for each section of the image; choose a variety of grains to provide contrast. Mark each section of the drawing to indicate which grain you intend to use to represent the section in the finished inlay. Mark the original image, and save the copy to create your pattern from.
Cut out the outline of the image on the copy, using scissors, so that you leave the outside outline of the image in the paper. Save this to use as a template to mark the background piece for the inlay.
Separate the sections of the copied image using scissors to create a paper template of each section. Apply spray glue to the back of each paper piece and stick them to your veneer pieces, one paper template for each section of the inlay.
Cut the veneer pieces out, following the outline of the paper pieces with razor craft knife, staying as close to the pattern as possible. Remove the paper pieces from the veneer and fit the veneer pieces together to recreate the image.
Trace the outline of the entire image from the paper you cut the pieces from onto the wood surface you want to install the inlay on. Cut the outline into the face with the craft knife. Remove the wood from the inlay area using a sharp wood chisel to a depth equal to the thickness of the inlay veneer.
Apply wood glue to the backs of the veneer pieces and fit them into the chiseled outline. Cover the inlay pieces with wax paper to prevent the glue from sticking. Place a piece of hardwood over the inlay. Clamp it in place with wood clamps, or place a heavy weight on top of it.
Allow the glue to harden. Sand the surface of the custom inlay smooth with 220-grit sandpaper.