Answer : Some people use simple programs like PowerPoint or Google Drawings, while others use more sophisticated software packages like AutoCAD or SketchUp. Whichever method you choose, the basics are the same: you start with a basic outline of the room and then add in all of the cabinets, appliances, and other features.
One important thing to keep in mind when designing your kitchen is scale. Make sure all of the elements in your design are properly sized so that they will fit in the actual room. You may also want to create a "virtual tour" of your kitchen so that you can see how it will look from different angles.