Here's a few of the basic alterations listed in the Eve Classic pattern (used with permission).  

These alterations are applicable to other patterns, though, if you have a pattern you're trying to alter to fit. If you remember the different torso shapes like this image from SizeCharter, torso shape affects the cup fit also. 

If you are shaped like the Hourglass, or Inverted Triangle, you may need more space in your neckline area. While is you're more like the Pear, Rectangle or Round body shapes, then you may need to pinch out space in the neckline. 

These images below feature various alterations that one might need. Some of them address assymetry. 

Another common alteration is to move the apex.  This is something you'd do if the bra (or your body) is causing your nipples to point outward in what bra makers call  an "east/west facing" direction.