KeepAndShare.com gives this example of a good best man toast: "I'd like to propose a toast to the bride and groom. May today be the beginning of a wonderful new and long-lasting chapter in their lives, and may they always love, honor and cherish each other, just as they do today." The toast is typically the last part of a longer best man speech.
During the best man speech, the best man typically talks about his shared history with the groom or the couple, relates anecdotes or gives marital advice. The toast at the end should express best wishes to the couple for a long and happy marriage. The best toasts are personalized, but examples are available online.
BerkshireBride.com recommends tactful but humorous toasts, such as "Here's to you, bride and groom. May you experience nothing but green lights, no potholes and great driving music on your highway in life adventure together! Congratulations, and I wish you all the best!"
TheKnot.com suggests using a meaningful quote by an author or famous person the couple admires and writing the toast on a card to give the couple as a keepsake. Regardless of the words chosen, the toast should never be inappropriate or embarrass the couple.