The most important thing when choosing your underwear is knowing what you are going to use for, is not the same the sports kind than the one you would wear at a party or for special evenings.
It is interesting to know the sizing of the brand you normally use because you know it fits well and you like how it looks but also try other brands and remember that just as you found your favourite one you can find others that may be equally good or even better.
Choose the color of you lingerie depending on the rest of your wardrobe, try to make what you wear consistent with what you want to convey.
Talking about price, there are an infinite number of brands currently on the underclothing market, not always the most expensive ones are the ones that fits you best, so have a look at the lace, embellishments and those little details that make part of your personality.
If you have a small bust and want to get more volume, you can find those bras that with padding. If you have a normal size bust I recommend you to use the normal kind, there are few on the market but will give you a natural appearance. Remember that the style and harmony of what you wear is up to you.
Shirley Jacome Navarro