Writer: Ctrl+S save, F12 save as, Ctrl+K link, Ctrl+Enter page break, F7 spell, Ctrl+Alt+1 heading.
Spreadsheet: F2 edit, Alt+= AutoSum, Ctrl+Shift+L filter, Ctrl+PageDown next sheet, F4 $refs.
Presentation: F5 show, Shift+F5 from here, Ctrl+M new slide, B black screen.
Print this page (Ctrl+P) and hide the site chrome via your browser’s print backgrounds off.
Learn four, ignore the rest for a week
New users stall by hunting every shortcut. Memorize Save As (F12), Find (Ctrl+F), Heading 1, and AutoSum. Everything else is a bonus. If a shortcut does nothing, you are in a UWP build or a language pack remapped Alt sequences — search in-app Help for “keyboard” rather than assuming the suite is broken.
Print layout for the cheatsheet
Landscape, two columns if your browser supports it, margins 1 cm, hide this site’s header via the print dialog. Tape it until F12 is reflex. Then recycle it. A cheatsheet you never take down is wallpaper.
Mac
Ctrl in the tables is usually Cmd. F-keys may need Fn. If Cmd+S fails, the focus is on a task pane. Click the page. UWP-on-Windows vs Mac will not match every Alt sequence — do not memorize Alt chords from a Windows blog on a Mac.
Do not hunt custom remaps first
If Ctrl+S fails, focus and Fn Lock are likelier than a secret keymap. Custom ribbon remaps are a power-user hole. Reset to default if you inherited a profile from a “tweaks” YouTuber.