How you present yourself on stage. If you are performing solo or with a band, you have to make the audience want to watch you. Improve what you've got. You could be the best singer in the world, but there is always room for improvement. If you've never had formal training, it's never too late to start.
Breathing properly is one of the key elements to singing.
If you breathe primarily from you upper chest, you are not singing correctly. You are straining your voice. You must breathe from your abdomen and push that sound out. Sing it your way. That makes you stand out.