Twenty Twelve Front Page

Just started with WordPress and using the TwentyTwelve Theme. I’ve seen some reviews showing the top of the frontpage in two colums with text to the left and an image to the right, with a further two colums underneath containing widgets. When I create my front page the text wants to be below or above the image, how can I get the text to sit to the left of an image. I know this is likely to be basic, I’m just starting and also only have a basic knowledge of CSS.