Copy: Select text or files → Press Command (⌘) + C
Paste: Place the cursor in the destination → Press Command (⌘) + V
Copy (right-click): Select text or files → Right-click → Choose Copy
Paste (right-click): Right-click in the destination → Choose Paste
Cut: Select text or files → Press Command (⌘) + X
Paste and match style (text): Paste → Press Option + Shift + Command (⌘) + V
Paste from clipboard history (if enabled): Press Command (⌘) + V → Choose from the paste options/clipboard panel