Urgent Amtrak Question

<p>I’m going to go home for the weekend. It’s kinda a last minute thing if you haven’t noticed. As such, I can’t get the tickets delivered or even finish the reservation process. I know you can use the bus without a ticket then pick it up in Van Nuys. But what does that mean exactly?
Can I get on without a ticket or reservation and simply buy them in Van Nuys?
Or do I need to get a reservation for Van Nuys-Hanford(my destination) then pick that up in Van Nuys?</p>