Confidence comes when you know you will be successful. If you don’t know that you will be successful you can’t have confidence.
What you need is courage. Courage to take the next best step. When you do that, you move forward. Eventually you reach a point where you know you will be successful, and you can have confidence.
The trick to having courage is to install a process so you know what to do next. When you know what to do next, and then next, and then next and then next again you end up with confidence.
Whether you are delivering a presentation, selling a product or fixing a car, if you don’t have a process…buy one.