SewingThreads ok, one more for today. The most common fit error I see when sewing: picking your size based on your bust measurement. Best practices is the bust measurement is based on a B-cup. we like this. this is good. this gives a standard from which to go by. if you're using a company that alters this (sigh), then adjust accordingly. for example a B cup is 2 inches larger than your band - don't use upper bust because the variable muscle tissue there creates a false metric.