Misbehaviour of my labrador?

hello... i have 1 yr old lab... he is extremely naughty.... i am facing many problems with him... he picks up things and starts running and expects me to run after him... he loves water... and spreads himself wherever he sees water.. be it dirt... he gets extremely excited when he sees a new person and starts pouncing on them... he is hyper active... i have tried hitting him a be strict but doesnt work.... i have trained sit down and handshake and does all this only when he's on leash.... i live in a bungalow and my family members just hate him.. pls help...