# To move a line up
ddkP # delete line -> move up a line -> paste above the current line
# to move a line down
ddP # delete line -> paste above the current line
# to move a line <number> times up
dd<number>kP # delete, move <number> lines up and paste above
# to move a line <number> times down
dd<number>jP # delete, move <number> lines down and paste above