But forgiveness cannot be possible unless we admit that we have sinned. Imagine, if we claim we have not sinned, then the world would be living in unity and sharing. But it is not. Unless we admit our sinfulness, God cannot forgive us.
Second, know that God is the one who forgives and not just ourselves. When we forgive we are sharing in God's power to forgive.
Third, we need to realize the fruits of forgiveness - the state of becoming whole and well, uniting with God, healing, restoring to life.
We should be more concerned about this than inflicting pain, hatred, and vengeance against those who sinned against us.
Forgive then; forgive endlessly.