Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 882)

Registering Menu Items on My Menu Tabs
1.
Select [MY MENU*: Configure].
2.
Select [Select items to register].
3.
Register the desired items.
Select an item, then press < >.
Select [ OK ] on the confirmation screen.
You can register up to six items.
To return to the screen in step 2, press the < > button.
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