Kill & Yank (Cut/Copy and Paste)
C-space
Set the mark
C-w
Cut (kill)
M-w
Copy (kill)
C-y
Paste (yank)
M-y
Paste (yank) next saved selection
C-x h
Set point to start of buffer and mark to end of buffer (select the entire buffer)
C-x C-x
Swap point and mark