Canon EOS-1D X Mark III Advanced User's Manual page 770

3.
Add a checkmark [ ] to items to display.
Select information to display and press <
Repeat this step to add a checkmark [ ] to all information to display,
then select [OK].
Note
Regardless of the [ ] setting, relevant information appears in the viewfinder when
you press the <
move the lens focus mode switch, or turn the focusing ring of an electronic MF-
equipped lens to switch between AF/MF (
> / < > / <
770
> to add a checkmark [ ].
> / <
).
> buttons,