According to the expectancy theory, a manager wanting to motivate using instrumentality should

According to Expectancy theory a manager wanting to motivate using instrumentality should propose a reward for meeting the expectations for the job or the objective the person had to meet. This reward can be a pay increase, a commision, a promotion or a recognition for the job done.

Explanation:

The Expectancy theory proposes that a person will act in a certain way because they are motivated to choose one behavior over other due to what they expect the result of that chosen behavior will be.

According to this theory, Instrumentality is the belief that if the performance expectation is met, an individual will receive a reward for this.