Waist: Circle your waist with the tape (as if it was a belt) at your waistline, which is situated on top of your belly button and under your rib cage. (The line that forms is your natural waistline while you bend to the side) If you suck in your stomach, you will get a false measurement, so stay natural!
Hips: Measure the circumference of your hips, starting at one hip and wrap the tape measure around your back. Then, around the other hip, until you have it back to where you started. The tape has to be over the largest part of your buttocks.
Chest: Place the end of the tape measure at the fullest part of your bust, cover it around under your armpits, then around your shoulder blades, and back to the front.
Thigh: Measure the circumference of the fullest part of your thigh. Wrap the tape measure around your thigh from front to back and then around to the front.
Upper arm: Measure the circumference of your arm. Wrap the tape measure around the widest part of your upper arm from front to back and around to the start point.
Sleeve length: Place your hand at your waist, then start at the middle of the back of your neck and measure to your shoulder, down your arm to the elbow, and then on to the wrist.
Maybe you will need someone to help you with the measurements.
If you have a garment that fits rightly, measuring the piece of clothing rather than your body, can be a good replacement!