You install PDAnet on your phone, then turn on Bluetooth on your phone. Open the PDAnet app on your phone and select "Bluetooth tether". You don't need to install anything on your SP3, you just need to pair the SP3 with your phone.
I tried this and was unsuccessful at making it work. I could pair the 2 devices, the SP3 would show "connected" to the phone (I have a LG G2 phone) for only a few seconds and then it's status would change to "disconnected". I tried this many times with the same result. You may have better luck.
If you can't get Bluetooth to work, you might try enabling "USB tether" in PDAnet on your phone, then connecting your phona via USB cable. PDAnet will install some drivers on the SP3 and a small program running in the System Tray that will allow you to connect via USB cable. I have used that with my phone and it works well.
The best way (IMO) is to use PDAnet to create a wifi hotspot on your phone, then connect the SP3 to that hotspot via wifi as you would connect with any other hotspot. I use that method with my phone and SP3 and it works great for me.