How to edit Blog Post full display page format
I'm trying to make some changes to the Full Display page of Blog Post. This is partly because if multiple Categories are allocated to the post (and some of my blogs have lots of Categories), they come out as a long, single-file list ahead of the article content, which is then pushed down the page. I want the Categories displayed in-line at the end of the article, before the social links.
I've successfully made that change to the Blogs Post listing page, but absolutely nothing I do in Views or Context or anything else I can find in the Admin menu makes any difference whatever to the Full Display page.
Where do I go to edit the Full Display page format?
Many thanks in advance.