Changing the Plurk Timeline background is the most important thing to change on your Plurk theme.  This is where all the Plurking happens, so it’s the most important aspect of your Plurk Design.  Don’t sweat it, it’s easy.  Just enter the following code:

#timeline_holder {
background-image: url(http://www.yoururlhere.com/yourimage.jpg);
background-repeat: repeat;
}

If you are not sure about where the background image is located, you can right click on an image and choose “View Image”.  Than copy the location in the url bar at the top of your browser.