Final answer:
A department supervisor should professionally communicate specific accomplishments and contributions of an employee that align with company goals, and directly advocate for a pay increase based on these merits.
Step-by-step explanation:
The best way for a department supervisor to advocate for an employee's pay increase is to directly communicate the employee's accomplishments and contributions to the company's success. This communication should convey how the employee's performance aligns with the company's goals and interests, highlighting specific achievements and metrics of success when appropriate. Timing is also pivotal; while annual reviews are traditional periods for discussing compensation, if the employee's performance merits immediate recognition, it may be beneficial to address it sooner with management. Formal documentation and a well-structured rationale will support the case for the pay increase. It is important to maintain a professional tone and focus on the positive impacts of the employee's work rather than comparing them negatively to their peers.