Don’t be afraid to make mistakes. If you don’t ever make mistakes, you’re not trying hard enough.
More importantly, don’t be afraid to admit those mistakes and make changes to your strategy quickly.  It’s far worse to hide a mistake and continue on a failing path.  It’s also far worse to admit a mistake and then NOT try something different. I love the old adage “The definition of insanity is doing the same thing over and over but expecting different resultsâ€.