Some people don't realize that inner peace is their choice. Learning to live with inner peace is totally worth the effort.
You have to learn to control your emotions, which is not so hard as it seems. All you have to do replace thoughts. It means that every time a negative thought comes to your mind you have to get rid of it and replace it with another positive one. Don't let circumstances determine the way you feel. Try to see something positive in every situation. If someone's rude to you, don't respond with a fiery comeback. Perhaps they've had a bad day and they didn't mean to be rude. Don't let negative things affect your state of mind. It's up to you whether to be happy or not.
Probably the most important thing about achieving inner peace is acceptance. Stop trying to control everything around you because you can't. Accept things the way they are. Don't be judgmental of others because you're not in their shoes. Of course a lot of bad things happen in life but you can't change the world. What you can change is your attitude. Forgiveness is essential for living with inner peace. Don't let past events taint your future. Everyone makes mistakes. You shouldn't be sorry for anything you've done because you've chosen the alternative that's been best for you at that very moment. It is normal to see things in a different light when time passes. The point is to learn from your mistakes not to be sorry for them. By forgiving yourself, you free your mind and spirit from thoughts which prevents you from being happy. Do what you love, no matter whether it is some kind of a hobby, sport or just hanging out with friends. Having no time for fun is not an excuse. If work is the only thing you do, you'll destroy yourself after a while. Human beings are complicated. You don't have to do only what is expected of you but what you truly enjoy, desire or dream of. Doing what you love helps you express who you truly are, which will contribute to achieving better inner peace. Spend more time in the nature. Walking along a forest path in a sunny day, for example, can help clear your mind of everything that bothers you. What is more, spending some time alone in the nature can help concentrate and muse on things that are important to you. It will help to restore the relationship with yourself. We're part of nature. That's why it has such a positive effect on our emotional and physical well-being. Don't expect too much. If you always expect everyone to act the way you think is right or do what you think is proper, you'll be disappointed. If you want to live a perfect life where everything is the way it should be, you'll be disappointed. Nothing's perfect. Everyone has their problems and try to cope with them. Don't worry about each single detail in your life. Just let things happen. After finding inner peace you have to do anything possible to keep it because that's the way to make life easier.