Our plugin can integrate with the free version of the Advanced Custom Fields which can be downloaded from here. It can also be downloaded directly through Plugins > Add New and then search for Advanced Custom Fields.
You can find all the information you need to install, setup and use Advanced Custom Fields on their website here. It is important you have a custom field group already created before following this tutorial. If you do not know how to create a field group, please click here to read on their tutorial on this.
The location box allows you to create a set of rules which decide when and where to add these fields to the edit screen / post object. Go to your Field Group > Location. You will want this field group to appear only on the Customers Details page therefore you will want this configured like this:
Customer - is equal to - All
Currently, our plugin only supports integration with the free version of Advanced Custom Fields. Integration for the Pro version is still under development as the logic is different.