A person making a short wedding speech should prepare it a couple weeks before the wedding, focus on specific details when speaking and tailor the speech to his own style. He should determine what type of speech is expected before writing it.
The speaker should prepare his speech beforehand because public speaking is more difficult without preparation. He should also write notes to use while giving the speech, unless he's confident in his memorization ability.
A typical wedding speech has four parts. It begins with the speaker expressing how happy he is to be at the wedding, and thanking the appropriate people. He then includes a personal memory. He encourages the couple and gives them advice. He concludes the speech by toasting the couple.
Focusing on specific details draws the audience into the story. Instead of simply describing the bride or groom, the speaker should tell stories that demonstrate those qualities. This makes the audience more interested than hearing generic compliments.
The speech should work well with the speaker's personality. If he is good at telling jokes, he should use humor in his speech. If he is a serious person, he should keep most of his speech formal. He shouldn't try to create a speech that he isn't comfortable delivering.
The speech should be between one and five minutes. The ideal length is one that keeps the audience wanting more, without growing tired of listening to the speaker.