It would be helpful if you can post what's going wrong, or where you get stuck.
Installing a blog is usually like installing any other module...
- Download the blog-module, unpack it locally on your hard drive, rename it to "blog"
- Upload the blog directory to the root of your silverstripe installation, you'll now have directories like "cms", "mysite", "sapphire" and "blog"...
- Log in to your silverstripe-backend and visit http://yoursite/dev/build/?flush=1; that will build the database entries for your blog and create some dummy entries.
- In your SiteTree there should be a new BlogHolder with a BlogEntry now
- Profit :-)
Notice: it might be helpful to put your site into "developer mode" before you start, to see any proper error messages.
Just add this to your /mysite/_config.php:
Director::set_environment_type('dev');
Must get ready for some serious partying tonight :-)
Cheers,
Christian