The three most important measurements for dress sizing are Bust, Waist, and Hips. Bust is also important for determining shirt size. Waist and hip measurements are critical for skirts, pants, and underwear. Grab a tape measure or string, and following these quick and easy steps to measure yourself.
Bust:
Measure around your body, under your arms and over the fullest part of your bust. Wear the bra you plan to wear with the garment when you are measured.
If you are planning to wear a strapless dress or top, then measure your self with several different strapless bras. I have 3 grades of strapless bras; 1) Basic strapless under-wire, no padding, 2) Va-Va-Voom padded, under-wire bra for maximum lift and support, 3) Medium strapless somewhere in-between. If you are not planning to wear a bra, or the stick on cups, measure yourself without a bra. There can be a substantial difference between no bra and maximum support with padding.
If the top is just a little loose or too tight, consider switching bras rather than alterations. Often it is the same price, or less, to buy a new bra than to pay for alterations. Of course, if this is your Wedding Dress, a red-carpet outfit, or a garment that you will wear frequently then certainly have the alterations.
Waist:
Hold the measuring tape at your natural waistline (close to your belly button). The natural waist is usually defined as the smallest part of your waist.
Some curvy girls are actually a bit smaller just above the belly button. While younger or more athletic girls may not have a defined narrower part, so measure right at the belly button. Remember to keep the measuring tape comfortably loose (it should NOT dig into your skin). Breathing and eating are NOT overrated! Light-weight fabrics that are too tight often have the stuffed sausage look. Body shapers and seamless panties smooth and can hold it all in for a smaller waistline and hips.
Hips:
Measure around the fullest part of your hips and butt. Keep the tape comfortably loose to ensure that you will be able to sit and walk. For “regular” sizes, a good rule is to measure 8 inches below your waist. Petite sizes are usually 6-7 inches below waist. Tall sizes are usually 10 inches below waist.
Now that you have your measurements look at the fit of the garment. Is it snug or loose around the bust, waist, and hips? The largest part of your body determines size for fitted garments such as sheath or mermaid style dresses. Empire waist, or garments fitted on top and loose in the waist and hips are great for pear shapes and size is usually determined just by the bust measurement.