My step-daughter was married a couple of weeks ago. I was really touched by her MOH's speech. You could tell it was from the heart. Just start out by sharing with the group the relationship you have with her. Let people know who aren't familiar how long you've known her. Share some personal stories. Definitely, throw some humor in there. This is a happy day! If you were involved with the stories of when she met her groom to be or how happy she seemed when you were told, etc.......that would be perfect. And end with stories of the couple....wishes for their happiness, etc. Anything that adds to a more personal side of the bride/groom to the speech in my opinion, can't go wrong. You'll do great!! Have FUN! She chose you for a reason!!