|This page in a nutshell: When in a dispute, attempt to reach a compromise or declare a truce.|
Working on Wikipedia, you may occasionally get into a dispute with another person. That person may seem like a troll or a hothead to you, but it's usually best to assume that you are dealing with a reasonable person who is simply confused on a particular issue or has a POV different from your own. No matter what the problem is, flaming is not going to solve it. Try to reach a truce.
Take it slow
If the behavior of another editor has upset you, consider doing something else for a little while. Take a walk. Do some laundry. Allowing some time for both you and the other editor to cool off makes it much more likely the dispute will be resolved amicably. If your next move is carefully considered and rational, rather than ill-considered, you'll give the impression of being a more reasonable person, and you'll be much more likely to prevail. Also, giving the other person time to cool down means they will be more willing to listen to reason. They may even start to regret acting rashly, or forget why they very much wanted things a certain way. Instead of immediately using your second revert, mark the article as disputed (if it's important that readers know about the problem) and put a note on the talk page.
Lead by example
If you are in an edit war, end it now. Be the first one to go to talk, ask for protection, or place a generous note on the other's talk page. (Try very hard to give a compliment for every criticism, and to admit your own mistakes.) Obey Policy. Always strive for wikiquette. Maintain Verifiability. Consider joining the Harmonious editing club. If things are out of control, move to the next step on Wikipedia:Conflict resolution. Never flame, try to get a rise out of somebody or get too emotional. This is only an encyclopedia, mind you.
Give the benefit of the doubt
Practically everyone here cares about quality articles. No one (outside of a vandal) intentionally puts inaccurate information into an article. It is almost certain that they meant well with their edit. If you have reverted already, try to look again to see if there is a better way to phrase things. One of the best parts of the Wikipedia is the opportunity for constant improvement. Take this opportunity to make a quality change, write a necessary addition, or move on to write an original article elsewhere. It's very satisfying!
Seek other opinions
If you are unable to resolve your problems, despite having tried the above, you should seek input from other people. If the accuracy or neutrality of an article is in dispute, consider adding a dispute header (Wikipedia:Accuracy dispute or Wikipedia:NPOV dispute). Seek input from others by listing the article at Wikipedia:Requests for comment.