Techniques

Every single forgiveness method below is words that are intended to come before silence. This is especially true of the Oneness method, under Already redeemed

These are basic ways to forgive. They will apply to different situations, you may use more than one on a single opportunity (aka: a person that irritates you).

Ectoplasm
This technique is for those with a New Age background and more familiar with psychics and their energetic healing modalities.
*First, see the person's spirit as a ball of energy hovering around their body but not in their body. Whatever made them upset you, see their spirit/soul as simply hovering above or around their body. Even momentarily, believe the idea that they are just watching. The body that appears to be doing the stupid things or attacking someone has nothing to do with them. This technique brings peace to beginners unfamiliar with the Course.

Outside of Time
This technique is designed to broaden your awareness of time, and use that acquired awareness to undo those difficult situations where normal compassion and forgiveness just don't work. If someone is just arbitrarily angry and you have absolutely no explainable reason for it, this is a good method, because cause is centered on the ego.
*When thinking about the other person, see that body as one of many bodies acting in a play in the Universe. That play is already over, you know that, every Course student does. But to use this, think that everything that has happened exists in a single instant. Your past and future and when you got into the situation with that person, all happened at the same time. The reason you are angry is the key here. Try to meditate on this idea: "My path and their path were bound to collide. The ego placed my consciousness here so I would feel wronged by them, and placed their consciousness there so they would feel wronged by me. These bodies were always here and anyone who goes through these bodies will feel wronged by each other. It was a set up!"

This is one of the more advanced techniques, but sometimes you just can't use normal forgiveness when you're too busy stopping to ask "Why did that happen?" The ego is insane, remember.

Guilt's Doll-house
This is my favorite technique.

*Think of the situation you're in right now as a giant dollhouse. The ego lets its hands in and purposely sets everyone up to collide. It may be a direct smashing, or it may be a little more intricate. The workday is long so you're stressed, the dog chewed the cable, rats chewed the other half, and maybe your kid just smashed a window. All of these events are just side-effects of the "tiny mad idea", aka, your ego. It is moving all of the bodies, but remember that only it is moving. The consciousness behind everyone is still God's, whole and free. The ego is moving it, and they take credit for doing whatever they're doing, but it s not them.

This is best combined with the next technique.

Already in the Kingdom

*What you see in front of you is always God, but of course we can't physically touch it. Imagine as if everyone around you was at Home, in Heaven. Now, when someone makes an act that upsets you, try to see them as if they were wearing a filter. We'll call that filter Karma. It's like rose colored glasses, it makes them see things, or not see things, that either are or are not there. In other words, this perfect being is doing something like wearing drunk goggles. You still see them as a perfect being, but you no longer hold grudges as you know they are acting on the idea that they are guilty of something and must move that guilt over somewhere else. Maybe it's on you, maybe it's on someone else. Either way, it is not true, and simply realize that it is not there.

Supply
Joel Goldsmith provided inspiration for this exercise.
*If the person I am angry at realized they are an infinite being with infinite supply, they would see no need to act the way they did.
This applies to wisdom, health, money, anything. You can forgive using supply, it is a valid form of practice.

Already Redeemed

*The above Kingdom and Supply meditations can be quickly summarized as this. "Everyone is already at Home, in the Kingdom of Heaven. They act the way they do because they believe they lost it, and have to earn it back. They didn't."

We are One

Every single forgiveness method can be enhanced by the simple idea that "They are in the same location as I in spirit. We are both whole and at home with God. I am grateful that they and I are in the same location or there would be no peaceful home to return to." This also brings up the more advanced method of "I am in just as much control of this body as I am of their body. I perceive this one because my subconscious guilt aligns with the ideas in this body, but it is only happenstance. I am an observer just as much as they are. I do not believe they are guilty, as they are at Home in Heaven just as I"

The five sense lie is a common phrase in yoga discourses. The above meditation must be realized, not just repeated mentally.