Myspace has a new method of editing profiles. This instructable details the old way of profile customization, and still applies to people who haven't upgraded to "Profile 2.0".
Step 1: The basics.
The first step is to add the following lines of HTML to the "About Me:" content box. I put mine at the very top, so that it is easily accessible if I want to change it later. This will not appear on your profile, it is simply to alert the web browser of the person viewing your page that there is CSS between these html tags, and to adjust your profile accordingly.
Step 2: The body.
This tells your Internet browser that this CSS applies for parts of your profile within the body HTML tags, which is almost everything.
Step 3: Remove backgrounds.
table, tr, td
This will make your background completely visible, and erase all the assorted boxes that appear on your profile by default.