How to edit page style?

I’m using vSlider theme at the moment. I like the drop down features of the posts. But the posts seem to be aligned in the centre of the page and the sideboxes at the bottom. How can i change the style so that the utilization of space is better i.e. i would like to have a two sided column with posts on the left and sidebox on the right side of the page, without changing the theme?

Thanks.