I have always had a problem with finding dresses and tops with sufficient boob room for my big breasts. So many items would look lovely if only they had more coverage over my chest. It's not a good look to have one's bra showing but in order to make sure this did not happen I have previously had to opt for high necklines, which I am not a great fan of, or sizing up to fit my boobs, meaning that the fit elsewhere was oversized and baggy.
Fairly early on in my boob-clothing journey I found that I could wear a thin vest underneath tops and dresses to cover my modesty. However, this meant wearing an extra layer and in warmer months or in centrally heated environments this could be pretty uncomfortable. It also changes the appearance of clothing as the neckline looks very different but at least it meant I didn't have to settle for poorly fitting clothing any more.