Sewing troubles

I am not much of a seamstress, I confess. I bought some fabric last week to make another top for my daughter-in-law, and finally had time to think about cutting it out today. Obviously I need to have a refresher course in reading the AMOUNT of fabric required. I overlooked a minor requirement and now do not have enough to make said garment...not sure I can find more either. Perhaps the newest grandson will enjoy a bright red shirt or something!