When adding new fields to existing or new tables in Dynamics AX it is recommended that you use Field groups. The function of the Field Groups is to group the fields of the table in a logical grouping. The largest advantage to them is in the design of the form where that data will be used or updated. When you use field groups you are able to easily add that group of fields to a form or report in one step. You are also able to add a label to that group of fields.
To get to the Field Groups node expand the Tables node in the AOT. Navigate to the table in the AOT and expand that table to access the Field Groups node.
To create a field group in Dynamics AX:
1. Locate the table that you need to add the field group to in the AOT and expand that node.
2. Right-click the Field Groups, and then select New Group
3. Right-click the new field group, click the Properties, and then type a name for the field group in the Name property.
4. Open the table in a new AOT window by right-clicking on the table and selecting Open New Window. Then expand the Fields node.
5. From the new window, drag fields from the Fields node onto your new field group.
6. Save the updated version