The measurements that you definitely need to determine the size or ordering of "Custom" suit are your:
(1) Height; (2) Weight; (3) Circumference of chest - the fullest part of your chest (bust), around under your armpits, your shoulder blades, and back to the front; (4) Circumference of waist - your natural waistline is located above your belly button and below your rib cage; (5) Circumference of hips - make sure the tape is over the largest part of your buttocks; (6) Length of out seam - distance from waist to floor.
The process for getting your body measurements is simple. Following the tips below, you can certainly get a close approximation handling the measuring tape yourself.
Use a cloth tape measure, not a metal one. Place the tape measure at the locations, depict on sketch to get accurate measurements. Make sure that, when you circle your chest, waist, or hips, the tape is level and neither too tight nor too loose. Do not measure yourself over clothes.