How do you create multiple layouts in one theme? Most sites I create have several layouts for different content types. How do we select different layouts?
Have you read the tutorials yet? http://doc.silverstripe.com/doku.php?id=tutorials
There is a special variable called $Layout which will rendered a specific template that matches a custom page type you have created.
You can also make multiple themes and call them per page using renderwith() http://doc.silverstripe.com/doku.php?id=templates&s=renderwith#calling_templates_from_php_code