Extract the 2 programs (DS4Windows and DS4Updater) in the zip wherever you please (My Docs, Program Files). Launch DS4Windows. A windows will pop up showing how to install the driver, if not, go to settings and click "Controller/Driver Setup". If you have used SCP's tool in the past, you may need to uninstall the drivers to use the DS4 with bluetooth. Connect the DS4 via a micro usb or through bluetooth (DS4 Device name: "Wireless Controller") may need to enter pair code: 0000). All should be good to go once you connect the controller, if not restart DS4Windows, or even your computer.
Note: same games work with the DS4 without DS4Windows (however it does use rumble) Games like these can cause double input in menus (ie pressing down on the dpad moves 2 spaces) or the wrong button to do incorrect functions. To solve this, check Hide DS4 in the settings, if you see a warning in the log/text on the bottom, that means you must close said game or client that causes the conflict and reconnect the controller.