Bust Measurement: This measurement should be taken around the widest part of the bust. Do not pull the measuring tape tight, but make sure that it is a close fit. Round this measurement to the nearest half inch.
Waist Measurement: This measurement should be taken at your natural waist, usually located near the belly button for women (or a couple of inches below the belly button for men). If you're not sure exactly where your natural waist is, bend over to the side and note where the skin folds. Take the measurement at this point. (Don't suck your breath in, now!) Round this measurement to the nearest half inch.
Waist to Underarm Measurement: Starting at your side, measure the distance from your natural waist to a couple of inches beneath the armpit. The top edge of your bra is a good indication of where to stop measuring. This measurement is going to be the side width of your corset; don't make it too long, or your corset will bite into your armpit or hip. This waist-to-underarm measurement can vary widely; some short-waisted women have a 6 1/2 inch measurement, while very long-waisted women can have a measurement up to 11 inches long. Round this measurement to the nearest half inch.
Cup Size: This is the size of bra that you wear--A, B, C, D, or greater.
Center Front Length: The center front length is the length of the center front of your corset, from top to bottom point. For an early Tudor corset, which doesn't have much of a point in the front, you can use 12 inches; for a long, late-Elizabethan corset, the front measurement can be up to 16 inches. If you are short-waisted, 12 inches is also a good measurement to start with. If you are long-waisted, 14 to 15 inches is a good measurement to start with. This measurement isn't vital; once your corset pattern is designed, you can easily lengthen or shorten the front length without affecting the fit of the corset. If you have a wooden busk you plan to use in the corset, your center front length should be the length of the busk + 1/2 inch. If you want to measure the center front length on yourself, measure between the breasts from a couple of inches above the bustline (approximately the level of your armpit) to the place where you want the bottom point of the corset to be.
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