You must begin now. You can make it. You have what it takes to succeed.
This is the heart of a commencement speech. When you deliver a commencement speech, always remember that your audience is now obliged to leave the borders of their comfort zone.
You do not have to know the future, but you can always sell it to them. You have been there before too. You were afraid and uncertain.
You do not have to tell them everything, but at least, tell them that everything will be fine.
Everything will be fine because they can make it, because they are prepared, and because they can decide to succeed.
Not every one of us is given the opportunity to speak to them. You have that opportunity.
Tell them the truth. And give them courage.