Unless you're still in the growth stage (which is under 25 years old), your bones will not get bigger. You can determine whether you are small, medium, or large bone with a simple test:
(1) Wrap your right hand around your left wrist, touching middle finger and thumb of the right hand.
(2) If your finger and thumb touch, then you are medium boned.
(3) If your finger and thumb overlap by at least 1/4", you are small boned.
(4) If your finger and thumb don't touch by at least 1/4", you are large boned.