Please pick apart, comment, whatever. I've put it into the "Further reading" style FAQ, rather than the plain style. Thoughts?
How do I add a background image in S2?
Most layouts within the S2 style system allow you to add a page background image to your journal via the S2 customization area and is available for all users, regardless of paid/unpaid status. Details on which layouts allow this customization can be seen at http://www.livejournal.com/community/s2howto/16047.html.
To add a background image go to http://www.livejournal.com/customize/ and click on the button labeled either "Customize" or "Edit customizations". Depending on your layout, the area to add a page background image can be found either in the "Presentation" tab or in the "background" tab.
You can then enter a background image in the format of http://www.example.com/image.jpg. You will need to replace this example with the actual URL of the image you want to use as your background.
Any image you wish to add must first be uploaded to a webspace provider that allows remote loading to LiveJournal.
Some layouts allow you to set background image properties. Details on which layouts allow this can be seen at http://www.livejournal.com/community/s2howto/16177.html.
If you would like to add a background image or background image properties and your layout does not support it via the S2 customization area, then you will need to upgrade to a paid account or be an Early Adopter or Permanent account holder and create a custom layer which specifies a background image or background image properties. Further details on background images can be found in the S2HowTo journal (http://www.livejournal.com/userinfo.bml?user=s2howto) entry at http://www.livejournal.com/community/s2howto/4969.html.
How do I customize my journal using S2?
Which options are currently supported by each public S2 layout?
Why are my images not displaying? What is remote loading?
How do I buy a Paid Account?
What are the different S2 layer types?