There are three ways in which you can
turn the visibility of joint labels in the scene view on and off:
Use the
Display > Animation > Joint
Labels or
Skeleton > Joint Labelling > Toggle
Selected Labels to toggle on and off the visibility of
joint labels in the scene view for selected joints.
Set the visibility of a single joint’s
label from the Attribute Editor. To toggle
the display of a single joint’s label in the scene view, select
the joint, open the Attribute Editor, and turn Draw Label in
the Joint Labelling section on
or off.