I know that this has been done before on this board, but I would like suggestions about whick exercises are best to get rid of this situation, and what methods achieve the best results.
You can do things that make your chest appear larger:
1. increase the size of the underlying muscle
2. improve your posture with an all round weight training program
3. increase the size of your rib cage with stretching and wind sprints/HIIT
4. reduce the size of your waiste and hips/thighs