Confidence in a fashion portrait rarely comes from standing taller and smiling harder. The interesting images do almost the opposite.
A shoulder drops. The chin turns away. One hand interrupts the face. The model may look bored, amused, or completely unavailable. That tiny refusal to perform for the camera is what reads as control.
The clothes still matter, but they are no longer doing all the work. A sleeve can frame the jaw. A chair can turn a body into an angle. Hard light can make a cheekbone look almost architectural.

And eye contact? Optional. Looking straight at the lens can feel powerful. Looking past it can feel even more confident, as if the camera happened to catch up.
The trick is direction, not stiffness. Every gesture should look chosen, but not over-explained. Too much posing and the image starts shouting its own mood.
The new confidence is quieter. It leans, pauses, takes up space, and lets the viewer do a little work. The portrait is not asking for approval. It assumes you are still looking.