A quick way to improve your reputation is to do good deeds. Be careful: if you've recently developed a bad reputation, you might seem desperate or like you're overcompensating by doing a bunch of good deeds. This isn't a quick fix. You must do good deeds consistently for your reputation to improve, otherwise you risk seeming insincere.  It is hard and time consuming to build a reputation, but quick and easy to ruin it. Consistency is crucial to firmly establishing your reputation.  Get your co-workers coffee, or offer to pick up a shift if they need time off. Offer your friends help, like a ride or a hand before they need to ask. Go out of your way to make sure people are feeling okay if you sense there might be something wrong. There are a great number of ways to volunteer your time. Care for the elderly or disabled, community gardens and events, as well as church-centered opportunities all are great ways to volunteer.  Animal shelters are also great opportunities to help. By giving up your time in the service of others, you can do a great deal to improve your reputation.  If you're still in school, see what sort of opportunities they can help you find. Many public schools and colleges offer different volunteer opportunities for students. Some businesses offer volunteering programs that may come with perks. Talk to your supervisor or HR department to see what sort of opportunities they provide. Give talks or lectures at a local school, organization, library or civic group on a topic you know and that would be helpful for others. Become compassionate towards others with bad reputations. By being nice to those who are not thought well of, after having gained insight from your reputation experience, you can develop positive perceptions. Take the opportunity to see the people who have bad reputations around you that may be in need of a friend. Go above and beyond. Do something amazing. Learn to play a musical instrument. Win a scholarship or award. Run a marathon. By doing impressive things, you can improve how...

TL;DR in Vietnamese:
Làm việc tốt một cách đều đặn. Tình nguyện. Học hỏi từ tình huống. Gây ấn tượng với người khác.