Familiarize yourself with the business school where you will be giving the speech and the larger university. Immerse yourself in the history and traditions of the school and the university. This will give your audience and you the sense that you've been dealing with the university for a long time.
Start the speech with a pertinent story. Try using a story that can be intertwined into your speech. That way, you can open with the story and tie it into the ending.
Tell the students how graduating from that particular business school will give them an edge. If you are an alumnus, tell them how a degree from the school changed your life. If you didn't attend that university, quote a famous graduate.
Inspire your audience. Share with the students not only how their degree will help them establish themselves in the working world, but also how they can use that degree to make the world a better place. Challenge the students to go out, do well and make a better life for themselves and others.