Measure your floor plan, wall length and height, corners and angles. If you are planning upper and lower cabinets, a sketch for both would work well.
To help visualize your new cabinets, use cardboard boxes to simulate the size and placement of the cabinets. Check the walkways and the door space for your refrigerator and oven.
Check the height of your old countertop. Would it be better for you to be lower? Or higher? Now is the time to make your new countertop the perfect height for you.
Consider your kitchen appliances and their placement. Will you need to move your outlets? Make storage cabinets for them?
While you are in the planning stage, watch for hardware that you like. Consider handles, knobs, and slides.