Relax and enjoy your summer.
If you can be bothered to read the Wiki page on the English legal system, learn the history of equity and the common law, some stuff about the division of courts, and basics of criminal and contracts (actus reus, mens rea; offer/acceptance, consideration, intention to create legal relations). You don't need to spend 20 quid on a book: have fun with it. Look through the courts, click on the bios of judges and see how weird their backgrounds are. Create a web of connections that you will remember when you come to studying.