First Setup
What should you change on a brand-new EOS R6 II before your first shoot?
Format both cards in the camera
Formatting builds the folder structure the camera expects. This body formats one card at a time — pick Card 1, format, then Card 2. Shooting 4K video? Tick Low level format: Canon's own manual calls for it before 4K recording, and it clears every recordable sector.
Write every still to both cards
Out of the box the camera records to one card and the second slot sits idle. Set Rec options → Rec. to multiple and every still is written to both cards at once — if a card dies, the shoot survives. Its sibling setting, Rec. separately, cannot split RAW files, so multiple is the one you want.
Shoot RAW — know C-RAW
Set Image quality to RAW for the full file. Canon also offers C-RAW (Compact RAW): the manual states it produces RAW images with smaller file sizes than RAW — Canon's own approximate sizes are 26.1 MB for RAW and 13.2 MB for C-RAW, the same 6000×4000 pixels at about half the card bill. Default to RAW; reach for C-RAW when card space is the constraint.
Still photo IS: Always
Set Still photo IS to Always and stabilization runs whenever you compose, not only at the exposure. Shooting a lens that cannot communicate with the body? A Focal length item appears in this same menu — set the lens's focal length (1–1000mm), and enable Release shutter w/o lens under Custom Functions or the shutter will not fire at all.
Register everything to C1
Canon's saved setup is a physical dial position. Register the setup you just built to C1 — after any reset, firmware update, or borrowed-body detour, one turn of the dial restores it. Leave Auto update set. off for now, so experiments in other modes never silently rewrite your C1.
Do the five steps now, in order, then turn the mode dial to C1 and confirm every setting stuck. That dial position is your camera from today on.