Scarlet Witch's Ult

I love playing as Scarlet Witch, especially since I'm pretty good with her. HOWEVER, I can never get any kills with her ult. In fact, I'm typically dead before she finishes yelling. Literally what do I do? What's the strategy for it? I've even tried getting above, if the map allows me, and throwing myself off but I still get killed pretty quick lol Any help is greatly appreciated!