If you want to stop being selfish, then you've got to learn to compromise. This means seeing that it's better to be happy than to get what you want, that other people have needs too, and that you can't always get what you want. You don't want to have a reputation for being so stubborn that people wouldn't even think about approaching you with a difficult situation. Learn to listen to people, to weigh the pros and cons of any situation, and to be able to see the situation from another person's perspective.  Don't focus blindly on getting your way. Focus on understanding the situation from both sides. Ask yourself, "Who wants it more?" Do you really want this particular thing so badly, or are you just being stubborn for the sake of it? Not everything can be a priority for you. Make sure to hear the other person out and consider their perspective before you respond. Selfish people think that they deserve the best treatment and that they deserve to be spoiled, and that's just not the case. If someone does something nice for you, whether they are complimenting you or giving you a ride to class, you should be grateful and thank them for their actions instead of just acting like it's perfectly normal that they want to do favors for you. Don't expect kindness or understanding and be grateful when it comes your way.  Selfish people think they "deserve" the best treatment at all times. It's time to stop and think about all of the people who have really made your life better. Selfish people think that they have to choose every movie, plan every vacation, and get their way in every school or work-related project. Well, it's time to take a step back and to let some other people do some of the deciding. Sure, it may be scary to go to that new Thai place instead of your favorite usual Italian restaurant, and sure, you may not like letting Mary have so much control over your latest report; but you've got to trust that other people know what they're doing and to let them get their way, too.   Giving up control can help you...

TL;DR in Vietnamese:
Học cách thỏa hiệp. Cảm ơn mọi người. Ngừng kiểm soát. Ở bên cạnh những người không ích kỷ. Đừng ngắt lời người khác. Nhớ những ngày sinh nhật. Giữ liên lạc với bạn bè, gia đình và họ hàng. Khen ngợi người khác. Đừng huých mọi người khi đang xếp hàng. Có mặt đúng giờ.