How would you plan a hardware and configuration strategy for a new SQL Server installation supporting a large, performance critical application?

You would carefully size available memory to support a sufficiently large buffer pool for your expected data volume, choose fast storage such as solid state drives especially for tempdb and transaction log files, properly configure the maximum degree of parallelism setting based on your specific workload type, and separate data, log, and tempdb files across different physical storage where possible to reduce contention.

-- Example configuration considerations
EXEC sp_configure 'max degree of parallelism', 4;
RECONFIGURE;