From Jays2Kings:DS4Windows is a portable program that allows you to get the best experience while using a DualShock 4 on your PC. By emulating a Xbox 360 controller, many more games are accessible.
How to use:

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.