Open with an I.D. and a thank you.
If the emcee didn't introduce you, do it yourself, and mention how you know the bride and groom and for how long. Then thank the guests for coming to the wedding. It's a nice way of making them feel part of the toast.
Be heartfelt.
You and the bride are obviously very close. Telling a story about her that's sweet, sentimental, and short would be perfect.
Mention both the bride and groom.
While your focus will be on the bride, don't forget to mention the groom—your first impression of him, how you've grown to love him, or something else that's warm and personal.
Say something to get the crowd laughing.
You don't have to be Melissa McCarthy to use humor to great effect. There's no better way to win the crowd over than with a short, amusing anecdote.
Forget about sharing that hysterical college memory.
Sometimes there's a fine line between funny and embarrassing. Don't cross it even if you're sure the story is a winner. The bride's relatives don't want to hear any anecdote involving her underwear.
Avoid negatives.
That includes ex-partners, infidelities, health crises, or the rocky road the couple may have faced in their relationship.
Wish them well.
Glass raised, you should end with a loving toast wishing the bride and groom a long, happy marriage.