At the very beginning, when speaking to the blue orb, don’t chose the options “Love,” “A lover,” or “Friends,” and your charisma will be lower than if you choose them. Then, once you meet Silas, lie about why you’re there, and your low charisma will ensure he doesn’t offer to give you a ride, lest he be late to getting to the academy. After he leaves you, you’ll begin making your way to the academy on your own. That’s when you meet Aldric.