Place jam jars and any other containers you plan to use on the tray, first. It's easier to fill in your ingredients around them than to try to find a place for them later.
Fill in appetizer tray ingredients, one color at a time so that you have a visually-appealing variety of colors spread out across the tray.
Notes
These ingredients are suggestions. Feel free to incorporate whatever you like and omit anything you don't!
You can use a tray, platter or cheese board depending on what you have on hand.