Namespace Editor
The Namespace Editor show Datatype grouped into tab (LN, DO, DA, Enum, basic FC and Condition).

Namespace Editor View
For each element you have the properties view on the bottom of the screen where you can change Datatype element property.

properties of a namespace element
Put as much information as possible in your DataModel, check all the properties and give meaningful information on description field.
You can also open a second namespace or other scl file with the “Scl Model Editor” and split the screen in 2. Like this you can easily create your model by just “drag and dropping” elements from another model.

drag and drop to create new datatype
When you create your own namespace, you should pay attention to the IEC61850 standard especially in terms of which elements are mandatory.
Be careful, with element naming. It is currently not well support to have a namespace element type id contains in a other element type id (e.g. MY_XSWI is include in MY_XSWI_BCU). This can have impact on your project depending on the order of type usage. To remove this potential issue you should use always unambiguous naming for element type id (e. g. MY_XSWI and MY_BCU_XSWI) or use always a suffix (e.g. MY_XSWI_standard and MY_XSWI_special1).