Below is a how-to video that goes through the process required to set up a low-cost, two-channel sniffer using CANFDuino and the SavvyCAN open-source CAN sniffing software. Please see the the instructions on https://togglebit.net to get started before following the steps described in this video. Download the latest SavvyCAN from https://savvycan.com. Both projects have repositories on GitHub.