How your job can be the best?

You must recognise your true passions - concepts like knowledge or technology, job functions or skills, or people.
Think back to the times when you felt best about yourself, and note them. Think about a project you really enjoyed. List your most rewarding accomplishments.

Talk to the people whose advise you value, people who have worked with you, and who have watched you in action. Sit with them and discuss your strenghts.

Finally, if you are already doing something you love, make it rewarding by aligning yourself to the goals of the organization, contributing more than is expected, and taking every opportunity to learn.