If you are looking for a ways to increase breast size, then you should consider some non-surgical methods before you go under the knife. Breast enhancement surgery is something that costs a lot of money, and it can be risky too. There have been, historically, instances of breast implants bursting and while more modern implants are made from materials that are safer and less likely to burst there are still potential issues with the surgery itself - anything where your skin is cut open carries with it risk of infection.
There are other ways to increase breast size that might not be as marked as actually getting an implant, but that can help you to get an appealing bust. For some women, taking hormonal birth control can cause a change in the size of their breasts. This isn't something that you should take lightly - discuss the risks of birth control with your doctor before you take anything, and remember that there are side-effects.
For many women, supplements that promote estrogen are a good option. There are phytestrogens in plants that can be beneficial for people who want to increase the size of their breasts. You won't see a massive change in your body from these, but there will be some difference.
Another option is to look at exercise. You won't get 'bigger' breasts by exercising, but if you build up your pectoral muscles then your breasts will have more lift, and that is noticeable. You will find that your breasts are more prominent, and if your tummy tones up as well they'll stand out more.
Wearing a properly fitted bra is also a good idea. What a lot of women forget is that if their breasts sag, they look smaller. If they are flattened out and squashed, they won't look as good as they could either. Ideally, your breasts should be supported underneath, and held in place but not squashed. Many women are wearing the wrong cup size, and the wrong back size, and this can contribute to back pain, and also damage the collagen in the breasts in the long term, which can make your breasts more prone to sagging.
So, why not talk to a bra fitting specialist and see what they can do for you? It could well be that once you have confidence in your bra you will feel better overall, and you will find that you can get an increase in the perceived size of your breasts.
If you're trying to lose weight, be aware that it might come off your breasts first, but don't give up on your figure. When the rest of you leans out, you could end up with an overall better looking cup size, and breasts that flatter your size and shape. Remember that perky breasts are what most people love, and they are more appealing than bigger breasts in some ways - especially if the bigger breasts aren't all that flattering overall. Be patient.