Dress comfortably and loosely as you get ready for your ultrasound test. You could be requested to change into a gown for your ultrasound exam. It would help to abstain from meals and liquids for a set period before your exam. We strive to make appointments early in the morning for these examinations. Other tests will require you to have a full bladder before taking them. Your doctor will instruct you on how to get ready for an ultrasound scan.