There is a while still before Ruby should sleep, to wake up on time, but he chooses to sleep anyway. Better to wake up earlier, and use the early morning for whatever he'd want to spend the night doing instead. He writes about the evening in his journal and then to bed he goes.
What he decides to do in the morning is study some magic. But instead of trying to learn anything new, he'll grab a spell tome for one of the spells he already knows and try to get the theory behind his instincts, an explanation of what exactly it is he's doing. The Lesser Ward tome is a simple enough one for this.