I've done this 2 ways:

1. The manual way, using a large SQL script created from a number of smaller scripts from SQL Server Management Studio or created by myself. It can be tricky but not so difficult once you've created a few of them.
2. The automatic way - using RedGate SQL Compare. Much easier if you have access to it.
   When using both methods I would use require a Pre-Prod database (a copy of Production) for testing.