There are a couple ways to do this. 1 – create a class in your css first.
Example –
.custom-bg {
background: yellow;
}
Then near the bottom of the Page editor you can enter that class in the “Body Class” field on the pages you want them to be displayed.
There are other ways to do this, you can take a look here – http://my.studiopress.com/snippets/custom-body-class/
and here – http://designsbynickthegeek.com/tutorials/dynamic-body-classes
.
