Shopping for bras can be oh-so frustrating, especially if you can't seem to get the right fit. But this infographic offers a few pointers.

Created by lingerie company HerRoom, the graphic highlights some of the basics of bra sizing, such as measuring for cup and band size. It sounds basic enough, but what you might not have known about bras is the "sister bra sizes," which are the sizes surrounding your current bra size. This can help you quickly find a bra that fits better when the one you're trying on doesn't run true to size.

For example, if the band fits but the cup doesn't, change the letter but not the number (e.g., from 36C to 36B or 36D). To change the band size, change both the letter and the number, diagonally (see the graphic below for a clear example, going from 36C to 38B or 34D). And to change both the cup and the band size, adjust the number but not the letter (e.g., 36C to 34C or 38C)

Check out the full graphic below: