I've had a couple of conversations recently with fellow professional performers that might interest the aspiring performer greatly. The subject was showmanship. When it's not there, it shows.
When you are practicing, there's no pressure to perform. You can spend entire days immersed in your art. Trust me, I know the feeling, and it's terrific! It's great that when you get into your groove, everything else melts away - it's just you and your passion. But, if you have an audience to entertain, you need to "open the bay doors", and let them in to your fortress of fun.
Remember that if you are going to get up in front of people - if you had the guts to climb on stage in the first place - then you have the guts to let go of your inhibitions and reach out to the viewer.
Connecting with an audience will increase their enjoyment of what you are doing exponentially. It doesn't have to be difficult. Just looking at the crowd during your routine, or perhaps even ask them a question before you start one will let them know that you care about them being there. Whether it's for a minute or an hour, you've got to make them feel their time watching you is worth it. As I like to tell my clients/audiences, "This is LIVE entertainment!"
I head a story once about an incredible juggler who was doing dinner theater. This guy was just amazing - seven clubs, 8 rings - but most of the patrons paid little or no mind to it. "How can this be??" said an incredulous Mark Angelo, who had only been juggling for a couple of years. Answer: no audience interaction. They were watching TV.
So remember that if you have an audience, and especially if you are being paid to entertain that audience, it's your obligation to make a connection with them. If you remember to do this, you will BOTH find that you have more fun than if you went it alone.