The order in which the spaces between the fingers are stabbed varies. In North America, the most popular version is to simply stab all the spaces in order, starting from behind the thumb to after the little finger, and back again. In Europe, a more complex order is used. With the spaces numbered 1 (behind the thumb) through 6 (after the little finger), the order would be as follows:
as opposed to the American version, which would be thus:
It is the European ordering which is shown on camera in Aliens.