How should the bra center gore lie on the sternum?

Bra front

BTW you need to see it 
from the top.

The front of the bra should always lie flat against the chest.


   When the front does not touch the sternum but stays in the air, it means that the band is too big (and the cups are probably too small). The band is hanging on the breasts, and does not give the breasts any support. You´re just wearing a breast-cover.
   A band should lie flat against the chest, then it´s fitting the ribcage snugly and supporting the breasts from below. Remember that 90% of the support comes from the band, and only 10% from the straps !

   To calculate your correct band sizesubtract 5 cm from the measurement under your chest, then round down to the nearest band size. You don´t add anything to the measurement, much less round up, since a band that is looser than your chest will never give any support to your breasts. And it will keep riding up at the back. Would you wear panties that are wider than your hips ?
Once you´re taking a narrower band size, remember to simultaneously get a bigger cup size, because cup size is relative to band size. Most of the "my band is too tight" complaints are actually caused by too small cups (or too narrow underwires).
  Check out the correct bra size calculator.

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