Ensure all packing material is removed from the microwave. There may be cardboard or foam holders behind the oven door.
Wash the glass turntable and roller ring in warm, soapy water. Thoroughly dry both pieces and set aside.
Gently wipe the inside of the oven, including the inside panel of the door, with a warm, soapy cloth. Thoroughly dry the floor, walls and door.
Connect the microwave's power cord to an outlet. Leave at least an inch of space on all sides of the microwave if installing the appliance on the countertop.
Place the roller ring inside the oven and the glass turntable over the motor driveshaft protruding through the floor of the oven. The pieces should match, providing grip.
Fill a mug with cold tap water, place it on the turntable and heat for two minutes at full power. Carefully remove the water when the cycle finishes; it should be very hot, indicating that the oven is working correctly.