I am trying to add a blogging subsite to an already existing site collection. However, the site is heavily branded and I'm trying to figure out how to apply branding to the blog. Sharepoint 2010.
Hope this helps. I put together a free Master Page template for a blog. Branding blogs is tricky because they don't follow a lot of the same styles that a typical SharePoint site uses. So checkout my post on it and maybe you can at least use the Master Page and CSS files to point you in the right direction. Hope it helps! http://www.bentedder.com/bittersweet-a-free-sharepoint-master-page-for-blogs/
The branding for your page is apart of the masterpage. The following source is an excellent how to on applying custom master pages to subsites.
If you have other master pages and once you have the publishing features, go to site settings on your blog and open master pages page under look and feel and select one of the available masters. If you have there any mininal.master don't pick that one, it is specific for search sites.
If you are looking for a different brand without having the pain of customize manually a SharePoint master I recommend you to take a look on this post: