When you install the general Twinfield plugin for WordPress you have to enter some settings wich allows the plugin to communicatie with Twinfield. On this page you can read how to configure the settings of the Twinfield plugin.
The “Username”, “Password” and “Organisation” values are the same as the details you enter on the Twinfield login page: https://login.twinfield.com/.
The values for the “Default Company” and “Default Invoice Type” setting fields can be found on the following Twinfield pages:
Default Company » “Profile » Companies” or “General » System » Switch company”
Default Invoice Type » “Credit management » Invoicing » Invoicing types”
The permalink settings are optional and can be left empty.