Life is going to throw many, many surprises at you. Things you can't control, things you have to react to immediately, and things that nothing can prepare you for. Whenever you encounter these surprises...just follow your heart, your gut, and use your common sense.
For everything else...prepare!
If you want to decrease stress and increase your self-confidence, then prepare for anything and everything that can be prepared for.
Test or exam - prepare.
Job interview or audition - prepare.
Going for groceries or buying a car - prepare.
I can't tell you the number of errors, mishaps, and stumbles I have witnessed only because the person simply didn't practice or prepare beforehand.
You are your own best teacher, you will learn the most from the mistakes you are able to recognize and correct on your own.
You can't recognize or correct mistakes that you don't look for ahead of time.
Some people will tell you they work best under pressure and they will procrastinate until the last second. I always wonder how much better that person could have done if they simply gave themself the time to really work on something and to improve it before sharing it?
No one who is hugely successful at what they do, has become so on a whim or because of luck. They have put in the time, the patience, and the willingness to improve their areas of weakness.
And this is the thing...those surprises that life throws at you...you'll find that the more prepared you are in your daily life, the easier it is to handle the curveballs that are thrown at you.
Love you when you're ready!