Cloning my micro SD card

I am very new to Allstar and the Linux operating system. I have my RPi 3 set up and running with a micro SD card from the hamvoip website. I want to clone that card so I have a back up. I have tried using Win32disk imager and just can’t figure it out. I have read threads in this community to use the dd command on my pi. I have putty open and started the Asterisk software then went to bash shell and entered dd and nothing seems to be happening. I do have a second micro SD card with the original hamvoip image on it, I have not configured it for my node. Do I have to reformat this card before I copy my image to it? If so, do I use SD card formatter on my desktop computer running Windows 10 or do I format it in my pi? Sorry for all the questions, as I said, I am very new to this and just need some simple step by step (handholding?) guidance. Thank you so much for your help, sorry to be a pain!