The toast is a mini-speech with a definite structure to it – introduction, body and conclusion.
The purpose of proposing a toast is to honour a person or persons, an institution or, less commonly, an event. We should try to avoid proposing a toast to controversial persons or subjects because we are asking members to pay tribute to someone whose views they may strongly disagree with (and no one should be made uncomfortable in a Toastmasters meeting.)

A toast should normally last between 30 seconds and 1 minute. As usual, you begin by addressing the Chairperson and members of the audience.

A toast is structured as follows:
Address the Chairperson.
Introduction: Begin with an introductory sentence that lets audience know this is a tribute or honour.
Body: Mention a few reasons why you are toasting that person and what makes her worthy of a toast at this time. Do not mention the person’s name yet so as to create some suspense.
Invite the audience to fill their glasses and rise.
Then mention the name of the person you are toasting.
Finally, conclude by a short declaration to that person which members of the audience are expected to repeat after you, “To Santa Claus!” Keep your declaration down to 3 or 4 words so that audience can repeat it easily and in unison.

Example:

Mr./Mme. Chairperson, fellow Toastmasters and guests. Tonight I would like to pay tribute to some very special people. They are individuals who are contributing a lot to our successful launch as a new Toastmasters Club. Their dedication, behind the scenes mentoring, and spirited presence at our meetings speaks volumes about their gifts as leaders. We are truly blessed to be the beneficiaries of such special talent. Ladies and gentlemen, would you please rise, raise your glass, and let us drink to the health of these special members – To A, B, and C!