By pushing a LEVER at the end
The Big Bang Theory Season 12, Episode 17
(CROSSBOW LEVER DRAGGING)
Game of Thrones Season 4, Episode 10
You use this LEVER to draw the string.
Game of Thrones Season 3, Episode 2
If you'll kindly pull that LEVER.
Game of Thrones Season 7, Episode 2
Give me a fulcrum and a LEVER
and I can move the Earth.
The Big Bang Theory Season 1, Episode 2