This exercise is taken directly out of the book Modern Tarot, by Michelle Tea. One of the best tarot books I've ever read.
Set yourself up in a quiet and comfortable environment.
"Start by thinking about all the people you know and love, the people closest to your heart whom you adore without complication. Let your heart be filled with these people, feel the love they inspire in you, notice how that love energizes your body. Groove on it for a bit.
Next, think about some people you don't know enough too like to dislike. The person who delivers your mail, someone you see a lot in the coffee shop, the person who rang up your groceries, a classmate who sits on the other side of the room from you.
As you meditate on them, work to bring those feelings of love you had for your besties into your body. Know that, like your closest people, that have had tragedy and wonder in their lives.
All of them strive to be loved and strive for happiness; all of them have known pain and have cried. The Universe created them just like it created those you adore. Send them love and well wishes.
Once you've gotten the hang of this and you're feeling pretty lovey, select some people you can't stand. Frenemies, outright enemies. Home-wreckers and gossips, liars and extremists on the opposite political side of you. If holding so many of them in your mind starts to stress you out, just select one.
Know that this person, like all the others, has had tragedy and wonder in their life, has strived to be loved, and for happiness, has known pain, and cried. The Universe created them, just as it created those you adore. Send them love and well wishes. Summon the feelings and goodwill you have for those you love and for those you don't know and feel it for these people too. Stay with this part of the meditation until you feel you've made some kind of breakthrough.
This spell is actually a lifelong practice, or it can be. All you need is the practice of sitting and generating love, first for those who already have it, next for people you feel neutral about, and finally for those you are biased against for whatever reason. Compassion can sound like a flimsy buzzword in our culture, but it is actually tough work."
