Good questions, both of them. It does take some experimentation, especially when you're all relatively new to the craft. Usually, a focus is something that has personal relevance to you. I've seen people use divining crystals and the like that had been passed down generation after generation, and it held relevance through family. Others go about seeking objects and methods and don't find anything for years until one day, they see visions in the most random mediums.

For now, though, I do urge the use of these crystals for today's lesson. They're specially laced with trace amounts of psitanium to help students better guide their vision through it. Play around with it for a bit, see if you can make a connection of sorts, and then I'll open up the Psycho-Portal.