I just got Ultimate Magic, and in the depths of Chapter 2 I found a section on spellbooks with Preparation Rituals that basically give you a one-shot or very specific advantage for each day that you prepare 3 or more spells from that particular book. But there are no rules for making your own preparation rituals. Am I missing something, or are we as players/gamemasters supposed to just wing it in designing more of these for ourselves?