Standardize the location of common controls on
similar machines. For example, place controls in an
easy-to-identify sequence (from fan 1 to fan 2 to fan
3, etc.) or in a place where it is easy to identify
which control corresponds to which display
(placing the heat-controlling knob directly under
the temperature dial, etc.). In this way, the control
panels for similar machines should also look alike.
This will reduce errors in operation.