This assistance method is intended for assisting an operator in performing a task on a product (12). To that end, the method comprises a step of displaying, superimposed on a view of a scene including a monitored part of the product (12) on which a subtask of the task has to be performed, at least one assistance image (100, 136) intended to assist the operator in performing this subtask. Said at least one assistance image (100, 136) includes at least one highlighting image (100, 102) highlighting the monitored part.