A reference from USAUltimate.org
Spirited games result from mutual respect among opponents. Assume the best of your opponent. Give him or her the benefit of a doubt. You would want the same for yourself. But if you are thick-skinned, do not assume that your opponent is. Maybe you should think of this rule as, "treat others as you would have them treat your mother."
SOTG is not just some abstract principle that everyone adopts and then games run smoothly without effort. Close calls are made in tight games. Hard fouls are committed. SOTG is about how you handle yourself under pressure: how you contain your emotionality, tame your temper, and modulate your voice. If you initiate or contribute to the unraveling of spirit, the concept falls apart quickly. If you act to mend things (or at least not exacerbate the situation) by following (1) above, the game heals itself.
Ultimate has a long tradition of good-natured heckling. Heckles are friendly barbs, typically from non-playing spectators. Heckling can be fun, but taunting is unspirited and wrong. Harassing remarks after an opponent's foul call or close play are NOT heckling: they are abusive taunts which create unpleasant playing conditions and often escalate to acrimonious disputes.
It is a fallacy to argue that the stakes are so important that some aspect of SOTG can be cast aside. Time and again, great teams and star players have shown that you can bring all your competitive and athletic zeal to a game without sacrificing fair play or respect for your opponent.
There is no "eye for an eye." If you are wronged, you have no right to wrong someone in return. In the extreme case where you were severely mistreated, you may bring the issue up with a captain, tournament director, or even lodge a complaint with the governing body. If you retaliate in kind, however, a complaint may be filed against you. We recall point (1): treat others as you would have them treat you, not as they have treated you. In the end, you are responsible for you.
After a hard foul, close call, or disputed play, take a step back, pause, and take a deep breath. In the heat of competition, emotions run high. By giving yourself just a bit of time and space, you will gain enough perspective to compose yourself and concentrate on the facts involved in the dispute (was she in or out; did you hit his hand or the disc; did that pick affect the play). Your restraint will induce a more restrained response from your opponent. Conflagration averted, you may resume business as usual.
When you turn the other cheek, you know you've done the right thing. You may not hear praise, there may be no standing ovation, but people do notice. Eventually, their respect for you and their appreciation of the game will grow.
Compliment an opponent on her good catch. Remark to a teammate that you admire his honesty in calling himself out of bounds. Look players in the eye and congratulate them when you shake their hands after a game. These small acts boost spirit greatly, a large payoff for little time and effort.
Not only does the realization that your actions will be remembered for a long time serve to curb poor behavior, it can also inspire better conduct. Many old-timers enjoy the experience of meeting an elite player who remembers their first rendezvous on the field and recalls the event in detail. A good first encounter with an impressionable young player can have considerable long term positive impact.