Jesus had some good advice for achieving peace with others. There are usually two ways we lose peace with others, they do something against us or we do something against them.
In Matthew 18:15-17 Jesus said: Moreover if your brother sins against you, go and tell him his fault between you and him alone. If he hears you, you have gained your brother. But if he will not hear, take with you one or two more, that ‘by the mouth of two or three witnesses every word may be established. And if he refuses to hear them, tell it to the church. But if he refuses even to hear the church, let him be to you like a heathen and a tax collector.
In Matthew 18:21-22 Peter and Jesus had a conversation that deals with the other situation: Then Peter came to Him and said, “Lord, how often shall my brother sin against me, and I forgive him? Up to seven times?” Jesus said to him, “I do not say to you, up to seven times, but up to seventy times seven.” That seems to put no real limit on how often we should forgive others.
For a person to follow Jesus’ advice to have peace with others, it’s almost essential that they first have peace with God. I encourage you to read the page on this site, Peace with God.