Loki: A Bad God's Guide to Being Good by Louie Stowell

 Loki the mighty trickster god has been banished by Odin to live on Earth as an eleven-year-old school boy. There's just one problem. He's FORBIDDEN from revealing his AWESOME godly powers, Loki must do enough good deeds to earn his place back.
As he records the truth in his magical (judgemental) diary, it seems like Loki might be a lost cause...

There’s a whole world of Loki to read: A Bad God’s Guide to Being Good, A Bad God’s Guide to Taking the Blame, A Bad God’s Guide to Ruling the World, A Bad God’s Guide to Making Enemies, A Bad God’s Guide to Causing Chaos, A Bad God's Guide to Monster Hunting.