1. to turn on, to light (the most common verb for turning things on. And also for fires.)
Opposite (closest): ausmachen
2. to hit on someone (In sense of trying to flirt)
3. to spark interest (Very colloquial. Can be sexual but also about general curiosity)
4. to aggravate, to tease, to goad
5. to put on, to put up (for pictures and other stuff you hang on walls)
Opposite (closest): abmachen
6. to dress (ONLY for salads)