First off, you should be using a Source Code Control system.

Then you need to create an "Upgrade Schema" script that can be run in batch mode against your QA databases first and then, after all testing has been done, against your production database(s).

Watch out for automated tools that perform comparisons between two databases. They will not get it right or will only handle the "simple" changes. See: http://www.sqlservercentral.com/Forums/FindPost702354.aspx which describes a schema change that involved XML binding.

See the following post which describes our process.

http://www.sqlservercentral.com/Forums/FindPost474053.aspx You may wish to read the entire thread as a lot of the "experts" provided some good advice to this exact problem.