The place to start when you are designing your dream kitchen is with a dimensional diagram of your kitchen space. On a large piece of graph paper, draw the outline of the kitchen space, including any doors or windows that you will have work around while you design your kitchen. Accurately mark where your plumbing and electrical supplies are located. You can move plumbing and electrical supply points, but this involves more time and money, and it is always easier to accommodate existing service supplies into your design, if practical.
The design process of your new kitchen should be fun and rewarding for you. Take a positive attitude and a sense of adventure into the process, be open to suggestions, and together, you and your kitchen designer will be able to design a kitchen in which you will truly be proud of cooking.