By default it's: C-b [ Start copy mode C stands for CTRL, by the way. This allows you to scroll up in the window and place the cursor where you want to

By default it's: C-b [ Start copy mode C stands for CTRL, by the way. This allows you to scroll up in the window and place the cursor where you want to start copying, then: C-SPACE Set mark This sets the mark for copying, then you can move around and what will be copied will be hilighted with a background color. M-w Copy selection This copies the selection. Incidentally, M stands for "meta" and is nearly always usable with ESC, but often ALT will work in many terminals (some need a setting to enable it). To paste, go to the buffer you want to paste into and then: C-b ] Paste!