There are many things to consider if you want to correctly tune and optimize SQL Server. Performance tuning is definitely one of those areas where practice makes perfect. However, it all starts by having a good foundation to build upon.
This 5-day class offers comprehensive coverage of the SQL Server architecture, indexing strategies, tempdb, query plans, locking and blocking... The course teaches you how to create baselines and benchmark SQL Server performance, how to analyse workload and figure out where performance problems are. The solid foundation you need to start optimizing your own databases.
More info