While I don't personaly incorporate much formal design into my own landscaping, I did want to add a few examples and pictures of gardens to this gallery. You may still get some ideas for a specific area of your yard.
As you can see from the following pictures, the plants in formal garden design are neat, tidy, and orderly in straight or diagonal rows. Generally, the creators of this type of garden have a somewhat advanced knowledge of plants.
Depending on area, many formal garden displays will have an axes that the rest of the design follows in symetry. The lines of your garden are often clearly marked through colour or texture.