Use your past mistakes as teaching moments for the future. Show your boss your ability to improve by documenting the mistake and any insights you learned as a result. This is helpful for you in terms of preventing similar errors to come, and also helps demonstrate progress when you come up for evaluation at work. Many times an error paves the way for innovation. Share an idea with your boss about a way you intend on changing your approach, so these types of errors don't happen again. Any major changes will usually require agreement from your boss. However, brainstorming new approaches at least shows initiative. Take special care to manage your tasks. This way, you have the time to focus on completing them one at time so you are not risking making needless mistakes. Take this mistake as a chance to look at other things you may need to change about your work habits. You might need to clean up your desk to avoid losing important papers or find a better way to manage emails to avoid using the wrong email list. Getting clarification can save you time in the long run since you won't need to re-do things later. Don't feel like you are bothering someone by asking for help. If you are polite and considerate in your requests, others are likely to enjoy offering a helping hand. Pay attention and learn from those around you. Ask for specific and hands-on instruction so you can figure out what you were missing before and move on. Often, it is one step you have missed in the process or something small that makes a big difference. Show your appreciation for the help and be sure to implement the strategies you've learned. Actually putting new skills into play shows that you have gratitude and makes others more likely to help if you should need to ask again. If you feel like you never have enough time in the day while at work, imagine how much worse it could be if you need to fix another big mess. Start a to-do list and learn to manage your time better so you are not rushing through tasks and overlooking important steps. Beating yourself up can actually make the problem worse. Everyone makes mistakeseven your boss, at some point. Practice self-forgiveness and be sure that you learned from the issue so that it doesn't happen again. Your boss will appreciate the fact that you consciously made an effort to improve yourself after a mistake.

Summary:
Document lessons learned. Avoid multi-tasking. Ask for help when you don't know how to do something. Slow down. Don't be hard on yourself.