I'm heading to London for my second visit in July for a week or so. I had a great time on the first trip and plan to have even more fun this time around! Any recommendations on events, clubs, bars, restaurants, attractions? I want to live it up and let my hair down, any advice will be greatly appreciated! I can't wait!!

Piccadilly - go to a show. Guys and Dolls, We will rock you...heaps of different one's about.
Laze in the park (Hyde Park - my fave - St James' Park) hire a folding chair and soak up the rays before the night out.
Make sure to reserve a day to lunch at Camden Markets. Great variety of food - heaps of stalls, absolutely superb for people watching.
Can't recommend anywhere for the nights out. I am more of a sports bar type. Beer, footy/cricket/whatever and a good yarn.