Paddings and margins

Hi,
I’m a newbie.
I have lifestyle pro. All I want to do is make the content area ‘wider’. I want to essentially remove the padding -that outsider area around the whole content/header/footer, so all the content can be wider – life full screen with still the widget areas. I installed genesis extender thinking I could easily do it without code – but I can’t even manage to work that out!
Please help. Something so simple and I cant figure it out.