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.
A second basic consideration to make is which functions you want your new kitchen to perform. For example, if you are looking for a kitchen design that allows for guests to congregate and have chats before the main meal, then you do not want to choose a design that is enclosed in a different room. Luckily, there are numerous options from which you can choose.