Take the time to get it right. Mistakes are costly in time and money. Having to pay the price to go back and fix mistakes is a great learning experience. Now you know where you were wrong and the next time you are likely to not make the same mistake. People love it when you make mistakes. There is a whole TV show “America’s Funniest Home Videos” where people laugh at other people’s failure. If you are wrong then they have a scapegoat and somewhere to place the blame. Most people don’t want to put themselves out there and take on the responsibility. They do not want the chance to be wrong.
If you are confident in yourself and the work you do then show it off. Accept the challenge and the responsibility. You know what you are talking about. Show your work and explain why each decision was made. Just get it right the first time or be prepared to learn.