Go to Windows Start button and choose Control Panel.
Type "Device Manager" in the top right search box which says "Search Control Panel"
Choose "Device Manager" as shown in the screenshot below:
Click on the arrow button beside each description to expand the list as shown below:
Check if a driver update is necessary
Click Properties and go to the Driver tab. Here, you can see your current driver version.
Check the driver's version number and the version of the driver you have downloaded. If the driver number is newer than the one you have, an update is available and you can read up on it, if necessary.
Then, just searcch the installer you downloaded and run it like you would any other program. When you're done, you should have shiny new drivers ready to help you get the best out of your hardware.