Navigate to the courier setup. Configuration>Options>Couriers then click Accounts, Add Account on the Hermes courier.
Make sure its the Hermes courier, and not MyHermes. Below is the correct one...
You will be presented with a screen as below...
All the data required for this form you will need to get from EVRI directly. They should be able to give you what is required here.
FIll in the form with the data from EVRI, then set the dropdowns at the top of the screen to ACTIVE amd LIVE.
Once done, make sure to SAVE the form.
You can then go ahead and create any rules you need setting up. If there is anything you're unsure of then do contact CCP Support via the live chat or email.