You'll have more maintenance issues with a pond more than 3 feet in depth. Decide what shape you like. Your options are limited only by your imagination and budget. Look through some home and yard magazines for ideas. Check the local building codes regarding ponds in your area.
Some places require a fence to be constructed around ponds of certain depths.
You may also need a building permit. Ask your dealer about the requirements in your community. Be familiar with the electrical codes governing outdoor use of electricity and fixtures if you plan to have lighting. Consider how long you want the pond to last, how much you want to spend on it, how good your installation resources are, and how available replacement materials are. Remember that if you want to have fish, you'll need a mechanical filter to remove debris particles from the water, and a biological filter to help control nitrogen levels.