God's gift of forgiveness has been truly opened up to each of us. This is reconciliation. And now, we have been given the work of reconciliation until Jesus returns to finalise the reconciliation of creation eternally.
Here's a brief outline of the process for participation in Godly reconciliation as demonstrated in the Bible. There is much much more that could be included.
Sinner: Confess (tell the whole truth), Repent (express sorrow for your sin), Ask forgiveness (1 John 1:8-10). This is the process of reconciliation for the sinner who, having humbled himself, desires restitution of the relationship. If the sinner is not repentant, you'll need to turn to Matthew 18:15-20.