How can I dress with scoliosis?

As you like. Severe curves are visible to others, but milder curves are not. You may be more aware of your scoliosis than your friends and acquaintances. Looser clothing will tend to "hide" the curve. No one has a perfect body. Wear clothing that complements you.
Proudly. My recommendation. Be proud of your scoliosis and don't try to hide it. It is part of what makes you who you are.
Whatever comfortable. Scoliosis is a structural deformity of the spine. It may lead to poor self image. In point of fact, the word "orthopedics" means "straight children", and the symbol of orthopedics is a crooked tree. Both references to scoliosis treatment. The good news is that scoliosis is mostly cosmetic, and in idiopathic cases not a life threatening condition. Wear what ever makes you most comfortable.