Face north and ask the pendulum if the item is in that direction. Repeat for east, south, and west until your pendulum answers YES. As you walk around you should ask for clarification, for example, you can walk into a room and ask if the item is in there, using the YES or NO divination technique.
Keep repeating until you find the item If you cannot find a starting direction, use rocks to build a layout of the area you are in. For instance, a rock could signify a room, a building or any other geographical marker. Hold the pendulum over the layout and you will feel a little drop on the chain when you are in the right area.