This is the best image that I found and how to measure yourself for a dress, especially if you are a online shopper.
How to Measure Yourself for a Dress
Unsure of how exactly to measure yourself before buying a dress? Get a friend to help hold a cloth tape measure and follow these easy steps …
1. Put on a comfortable fitting bra. Wrap the tape measure under your bust and remember the measurement. Add 5 inches (12.7cm) to that measurement. This is your bra size.
2. Keeping both arms by your sides, measure around your chest at the fullest point of your bust. (This is where you friend comes in!). Subtract your bra size from this measurement to find out your cup size.
3. Now measure your waistline. Your waistline is the thinnest part of your waist just above your hips.
4. Measure your hipline. Take the tape measure around the widest part of your hips.
5. Finally, measure your sleeve length. Do this by placing your arm by your side and measuring from the back of your neck, down the back of your arm to the bend in your wrist.