Hi katejo, in shower, soap up breasts and run finger tips gently over whole breast and under the arm at the border of the breast. Also, the only surface bad sign is a dimpling of the skin, or rarely, an unusual rash. There are other ways to check, but this works well for me. The slippery soapy surface makes it much easier to feel. No need to press hard. Also check area of nipple around and under to the extent you can.