The configuration tab is only visible to users with Administrative privileges

PLEASE NOTE: If you do not completely understand how a setting works, please contact customer support before changing ANY setting. Thank you.

Once in the configuration menu, click the Gateways menu.

Once the gateways list loads, click the Add / Change Settings button at the top right of the list. The add new gateway menu will appear.

Select your gateway provider from the drop down menu.

Proceed to fill in your Merchant UserId and Merchant Password in the fields provided. 

Once done, click the Save Settings button.

Make sure you enable that gateway by sliding the status bar to show On.