First, you will need the Android Auto app installed on your phone. Give the app permission to access your contacts, music library, and whatever else it asks you. Then, hook your phone to the head unit with a USB cable. The app will ask you permission to do a bunch of other things, so keep pressing “accept” until it’s all ready to go. Once that’s done, make sure your phone’s Bluetooth is connected and that you have paired it with your car. If the head unit you bought doesn’t enable Bluetooth, you’re all set to go, just make sure to keep your phone connected with an aux cord. If it does and your phone has recognized the unit, everything is set!