Ex: Using UCS

Move the UCS origin

Make sure UCS Icon set at Show UCS Icon at Origin

Select the UCS icon

Click the square grip to make it hot

Move to the corner of the solid

Turn on the Grid Display on the Status bar

Solid show below the grid
The X, Y, Z remain the same direction

Face UCS

Home tab > Coordinate panel > Face

Move the UCS icon on the face of solid

X,Y axis automatically align with the face

Click on the face

The grid show the XY Plane align with the new selected face
But it does not easy to define the X or Y axis

3 Point UCS

Home tab > Coordinate panel > 3 Point

Specify new origin point

Specify point on positive X

Specify point on positive Y

XY plane align with the face

View UCS

Home tab > Coordinate panel > View

The UCS icon rotate

XY plane rotate aligh with the screen

Adding text

This is the best way to add text labels to the isometric view

Named UCS

Home tab > Coordinate panel > Named UCS

Single-click on the Unnamed

Rename to Text Input

Return back to World

UCS icon return to origin position

Select the named UCS from the list

UCS rotated to the new UCS

You can delete any named UCS by right-click on the UCS

Select Delete