Tabular Display Folders
(Note: This feature will not appear in BIDS Helper until version 1.6.1.)
Unlike Multidimensional projects, Tabular projects in SQL 2012 do not support display folders. This feature gap makes Tabular models less user-friendly since the field list in Excel PivotTables is longer and less organized than it could be.
BIDS Helper provides a UI for editing display folders on measures, columns, and hierarchies. All display folders are edited in the same place. Right click on the .bim file and choose Tabular Display Folders...

That launches the UI for editing display folders:

Tips:
- If a field is showing up under the "More fields" folder in the Excel field list, setting the display folder to a backslash (i.e. \ ) will cause it to show up under the root of the table, not under the "More fields" folder.
- Some client tools like Excel allow a field to show under multiple folders. In order to accomplish this, separate the two folders with a semicolon (i.e. Folder1\SubFolder1;Folder2)
Limitations:
- Note that some changes like reordering levels or setting format strings will wipe out the display folders. BIDS Helper backs up the display folders in an annotation on the database. That way, the Tabular Pre-Build feature can prompt you to fix this setting.
- Display folders are not supported in DAX clients such as Power View currently.
- Display folders are not supported on Tabular KPIs currently due to a bug in Analysis Services.