There are umpteen things that need to be done/set to properly configure SQL Server. Same for your server itself, and the SAN and san connectivity too. There are also a ton of things that you need to monitor to set up a baseline for performance and then to compare current performance to past to see if something is out-of-whack.
These things cannot truly be effectively covered in a few forum posts.
Best,
Kevin G. Boles
SQL Server Consultant
SQL MVP 2007-2012
TheSQLGuru on googles mail service