Prior to setting PayGate within Tickera, you need first to create a PayGate merchant account which you can do here.
Once you have created your merchant account, you can obtain your merchant ID and encryption key which you will need to be able to set it up with Tickera.
Now, head to Tickera Settings > Payment Gateways and select PayGate from the list of existing payment gateways to activate it and to be able to enter all the necessary credentials:
* for testing purposes enter 10011013800 as Merchant ID and secret as Encryption Key.