A lehenga is a skirt. Everything else around it is a decision, and most of those decisions are reversible, which is what makes it one of the more flexible things you can own.
1. The full set
Matched blouse, dupatta draped over one shoulder and pinned at the waist. Formal, traditional, and the right answer for a wedding ceremony. Keep jewellery to one statement. A neckpiece or earrings, not both.
2. Dupatta over the head
The same set, with the dupatta taken over the head and held at the crown. It changes the proportion entirely: the eye reads a long vertical line instead of a wide one. Best with a lighter dupatta, or the weight will pull all evening.
3. With a corset or fitted blouse in a contrasting shade
Break the match. A deep skirt with a blouse two or three shades away reads modern without reading costume. This is the version that photographs best in daylight.
4. With a shirt
A crisp cotton or silk shirt, tucked, sleeves rolled. It sounds like a compromise and is not. The tailoring at the top balances the volume at the bottom. Skip the dupatta entirely.
5. Skirt alone, belted
Treat the lehenga skirt as a skirt. A fine belt at the natural waist, a plain top, no dupatta. This is how a bridal piece survives past the wedding and gets worn again.
One rule
Whatever you do, let one element be the loudest. A heavily worked skirt wants a quiet top; a plain skirt can carry an elaborate one. Two competing focal points make both look smaller.