Graduation gowns should fit loosely and securely if ordered in the right size. Check the size chart before ordering and make sure you take accurate height and width measurements.
The sleeves of the gown should fall below your elbow but above your hands, while the hem should sit below your knee but above your ankle. Whether you wear heels or flats will not change where the hem falls, so don’t size up to accommodate this.
When zipped up, the gown should flow loosely, but not slide around. The cap should also be able to sit parallel to the ground on your head.
The gown is the foundation of your ceremony ensemble, which will also include a graduation stole and honor cords, so it is important that it is sized correctly to avoid tripping or being in the way on graduation day.