Measure from the top of the head to the floor without shoes.

Raise arms out to the sides and place measuring tape around the back and across the fullest part of the chest, just below the armpits. Lower the arms (chest will expand slightly). Take the measurement with one finger between the measuring tape and the chest for a comfortable fit.

Leave arms at the sides. Place the tape around the back and across the fullest part of the chest, over the arms. The overarm measurement is particularly important for those gentlemen with an athletic build, whose shoulders are very broad in proportion to their waists.

Place the measuring tape around the natural waist just below the navel.
Some people have disproportionately large hips or thighs compared to their waist measurement. It may be necessary to order a larger waist size.
Rental formal trousers adjust to three waist sizes (ex: 33-34-35). If your waist measurement is at the high end of the size range you may be more comfortable in the next larger size.

Place the measuring tape directly over the pants around the largest part of the seat. Be sure to remove all bulky objects from the pockets.

Place the end of the measuring tape at the top of the waistband, above the outer side seam. Extend the tape to a point 1 inch above the top of the heel of the shoe. Be careful to keep the tape straight and do not stretch it.

Place the measuring tape around the bare neck, just below the Adam's apple, where the collar would typically button. Measure loosely enough for comfort, by placing a finger between the neck and tape.

Place the measuring tape at the base of the neck in back. Extend the tape over the broadest part of the shoulder and down the length of the arm to approximately 1 to 1 and 1/2 inches below the wrist bone. The sleeve measurement is taken to the inch only. If necessary, round up to the nearest inch.