Wear comfortable, loose-fitting clothes for the ultrasound examination.
Other preparation depends on the type of examination you will have.
For some type of scans, you have to be on an empty stomach and may be instructed not to eat or drink for 12 hours prior to appointment.
Generally, a full urinary bladder is necessary for a proper ultrasound examination.
It is advisable to drink up to six glasses of water, two hours prior to your exam.