Use a soft measuring tape to measure your bust, waist, and hips. Ensure that the tape is snug but not too tight. For the bust, measure around the fullest part; for the waist, measure around the narrowest part; and for the hips, measure around the fullest part. it's often easier to tailor or alter clothing to a smaller size than to make it larger. If a garment is slightly big in certain areas, adjustments can be made by a tailor for a more customized fit.