Here are 3 samples of custom needlepoint belts for you to consider:
#1. This is an example of a rough draft for a belt having a French Cooking School theme that I laid out to send to a customer for their approval and edits. It is always helpful and actually cuts down on my design time ($$$$) when a customer can supply me with specific images for their custom belts.

#2. Code flag belts are always popular for both men and women and can be embellished using additional motifs such as an anchor, sail boat, yacht club burgee, etc.

#3. Here is a custom belt dreamt up by a loving aunt for her nephew, reflecting his extracurricular activities. In the end, we had to cut out 3-4 other motifs as we ran out of room on the canvas.

FYI: When planning the size of a needlepoint belt, remember that dependent on who finishes your belt, 4"-6" will be needed for the leather tabs on either end. Contact your finisher before you start your project.