1. Use the extension installer, click the Upload button and select the jcc.ocmod.zip package.
2. Overwrite files/folders as necessary (no core opencart files will be overwritten)
3. Login to the Open Cart admin section and go to Extensions > Payments
4. Find JCC Payments in the list of extensions
5. Click "Install" and then "Edit" the payment module settings
Note: Please provide your Public IPs to JCC, to whitelist them to be able to receive the callback notification.