Maybe the word manuscript is confusing. The Oxford American Desk Dictionary (2001) defines manuscript as a hand-written or typed text. That's what we're talking about for this speech. Just write out what you want to say and practice it often enough so that you can deliver it to your listeners without reading it. Look down at the text as needed to remember what comes next.
Remember that the key to a successful speech of tribute is telling your listeners what obstacles the person or organization you are honoring has overcome. Then tell them what remarkable contributions the person or organization has made to society despite all obstacles.
Make sure the person or organization you pay tribute to is a public figure—someone we could all learn more about if we choose to. These speeches will be fun to hear, and hopefully inspiring. And, they will give you firsthand experience in speaking from a manuscript.