To fire a stone thrower, first pivot to face the target following the normal rules for war machines. Then, nominate a model or building within the stone thrower's line of sight (ignoring other models within the same unit), outside of its minimum range and within its maximum range. Then, take the small round (3") template and place it with the centre directly over the target.

The template cannot be placed over friendly models, or enemy models from a unit that is engaged in combat, as the crew refuse to deliberately target their allies (although the shot might well go wide and hit friends by mistake as we'll discover later).