General rule is to keep software and DAWs on a separate physical drive to your OS/boot disk, and HDs should run at 7200rpm minimum (bad news for laptop users). Defrag often and don't save files to your desktop (for a number of reasons).
Most audio software websites/forums have an 'optimisation' guide in their FAQ sections, so it might be worth for one that's specific to your DAW. This will include stuff like turning off WiFi connectivity and reducing the number of background applications running.