WIHA
Magnetisation:
The magnetic field in the lower part of the cube gausses iron and steel components. To gauss a tool, move it back and forth through the centre of the magnetic field (the gap in the cube).
Degaussing:
Gradually exposing a tool to the diminishing magnetic field in the upper part of the cube will degauss it. First perform a back and forth motion through the upper part of the gap (as viewed from the middle), before moving two steps further towards the edge.