I bought that from Walterstones just before Christmas, I was standing reading most of it in the shop, so I thought I better.
I couldn't decide who to give it to as a present, my 15 year old daughter, my 17 year old son, or my mother. In the end I kept it for myself.
What I got from it was that I think it would be a fun exercise to write 16 year old me a letter. Something like
Dear Ernie, when that guy from Paisley picks a fight with you, he's not joking, so HIT him first. And when your cousin comes with an idea about starting a sandwich business, tell him to take a run and jump. and learn Spanih, it'll be useful, etc etc.