Gil Fronsdal leads a Guided Forgiveness meditation. In preparation for a Loving-kindness practice is a practice of forgiveness. Forgiving is difficult.
Taking 3 deep breaths, let your breath return to normal. Practicing forgiveness, it doesn't mean condoning or denying that something happened. A practice of forgiveness so that our hearts does not close, It means we're no longer holding resentment and forgiveness is a difficult thing to do and sometimes we need to be willing to start the process of forgiving, no longer holding the anger, and the hurt.
It is similar to metta practice that it involves repeating 3 phrases. And letting the meaning of the phrases work their way to our hearts and minds, to be able to extend the forgiveness.
For whatever harm I have caused others, may they forgive me. (Repeat 3x)
For whatever harm others have cause me, may I forgive them. (Repeat 3x)
For whatever harm I have caused myself, I forgive myself (3x)