If you are comfortable with the palette interface, and if scaling to
DIMSCALE is adequate for your needs, then,
1) create a palette item
2) right click on it
3) select Properties
4) choose "Auxiliary Scale" under the Insert header
5) set this property to "Dimscale"
If you use this interface, you can also control the properties listed
under "General," which includes LAYER, among other (related) things.
Otherwise, .