Step 1: Plug in your PS3 controller via the USB cable. Windows will see the controller, and it will seem like it installs drivers for it, but it will not work as a game controller at this point.
Step 2: Download, extract & install your driver:
Step 3: Run the ‘DS3 Tool’ that was just installed.
Step 4: In DS3 Tool window, click the Driver Manager tab.
Step 5: Select the driver (there should only be one listed), and click Load Driver.
Step 6: Click the Profiles Tab
Step 7: Click Enable
Your controller should now be functioning. You can click Game Controller Panel to open the Windows interface for configuring game controllers from here.