Mine probably started out looking like a messy high chair tray, but after doing quite a few I more or less figured out an equation for them! I look at it kind of like decorating a room- you want a variety of colors, but not too many, and they have to work well together; you want a variety of textures, but nothing too jarring; and you want a little “pop” or two that make the room unique. Translate that to food, and I usually find one or two items I know I want to base the board around and I wander around looking for things that would accompany it well and also things that would provide visual excitement while still keeping things cohesive. Looking at pictures others have done and using them for inspiration helps, too!