When someone insults or does evil things to us, whether it be physically, verbally, or emotionally, our normal human impulse is to strike back with the same hurtful treatment we receive. Unfortunately, it usually makes the situation worse. That's not how God works. When Jesus was whipped, beaten, and nailed to the cross, He did not strike back physically or verbally. In fact, He blessed them and asked God to forgive them. Whenever we find ourselves in a difficult situation, we should always look to Jesus for guidance. 
In this verse, Peter urges us to pour out blessings upon those who do evil to us. Easier said than done. How can we do that, and why would we ever do such a thing for someone who has hurt us or insulted us? Peter answered that question in 1 Peter 2:21-25. We respond with a blessing when given evil because that's what Jesus did for us. He took on everything that we were supposed to suffer and paid the full price of our sins with His blood so that we could be free and have eternal life. How can we not pay the blessing forward? 
There will be times when someone does evil to you or insults you. Before you react, think about how God has treated you when you insulted or did evil to Him. He showed you love and blessed you. Take that same blessing and pour it forward to another. And as we give blessings for insults and evil, we will obtain or "inherit" a blessing for ourselves.

Dear Heavenly Father, when someone wrongs me, please help me to respond with love and blessing rather than frustration and anger. If I have hurt or offended someone, I beg for Your forgiveness and mercy. Although I don't have control over other people's feelings or reactions, I can take responsibility for mine when there are conflicts. Please guide me in those situations and help me to handle them the way that You would. I trust that You will judge the situation fairly and grant me blessings as I give blessings to those who hurt me. 
In Jesus's name I pray. Amen.