Create an API key as described here , for the initial setup phase we need permissions to read/write contacts, readt contact lists, and fields. As we need to use the API to lookup the field ID's to craft our API request configuration
Create a list of Field Names you want to be populated for each new account and an example value for each (screenshots from an example contact are fine)
Temporary create a user for sovendus to access you emarsys dashboard as we need to check if our test contact has any issue.
Get the contact list id where the leads should be added to
Send the Newsletter System name, the API key, the name of the fields with example values and the contact list id to Sovendus
Once we confirmed that the setup is done properly, you can adjust the permission of the API key to just "contacts read" and delete the sovendus user as we dont need access to the backend anymore.