TITLE: How do I change the appearance of my comment pages or other users' comment pages?
By default, comment pages display in the site scheme that is used for any system LiveJournal page. For Paid and Permanent accounts using the S2 style system, comment pages will display in the journal's style unless they choose otherwise; however, free accounts, as well as any account using the S1 style system, does not have access to customized comment pages.
When you are viewing another user's comment page, you may see a different customization, based on that user's paid status and customization settings. To avoid seeing differently-customized comment pages, go to http://www.livejournal.com/editinfo.bml and select the "View comment pages in your journal style?" option. This option adds "style=mine" to the URLs of comment pages on your Friends page, causing other users' comment pages to be displayed in the same way that your own comment pages are displayed.
Even if you do not wish to use this new option, you can append "?style=mine" to the URL of a comment page at any time so it does the same thing. If the URL already has an argument attached to it, such as "?mode=reply" or "?nc=," then you will need to change "?style=mine" to "&style=mine."
FAQ 21 - paid account
FAQ 7 - customizing journal or community
FAQ 186 - changing appearance of the main LiveJournal pages