Here are some tips to help you order the correct size. If you don't have a measuring tape, use a piece of string and hold it alongside a ruler.
Chest / Bust:
Lift your arms slightly and measure around your body (without a shirt is best), crossing over the fullest part of your chest.
For casual shirts, find a collared shirt that fits your neck well. Lay the collar flat on a table and measure the ”top” edge of the collar. For dress shirts, measure around the base of your own neck, keeping one finger between your neck and the tape measure.
Place your hand on your hip with your arm bent at 90 degrees. Measure from the middle of the back of your neck, across the shoulder, and down your arm to the wrist.
Measure around your waist where your pants usually fall. Keep one finger between the tape and your body to ensure an accurate fit.
Stand with your heels together and measure around the fullest part of your hips.
Lay your favorite pants on a flat surface and measure from the crotch to the hem. For a shorter inseam, order an Ankle length size. For a shorter inseam and smaller overall fit, order a Petite size. For a longer inseam order a Long length size. For an extra-long inseam and proportionate fit, order a Tall size.