Having a good reputation at work and maintaining it is hard work. But if you wish to be promoted, commended, and grow in your profession, this is something that you would want to develop.
Act. Speaking is one thing, but acting is another. Never say anything that you are not capable of following up with actions. If you say you can finish a task on a certain deadline, then make sure that you do exactly that. What you are building here is your credibility.
Have a positive attitude. A person who whines and complains, even if he or she works hard would be remembered for the latter.
Ask help when needed. This goes to show that you know your limits and that you value the skills of your coworkers as well.
Be considerate of everyone. Treat them as how you would want to be treated by others. Listen to opinions and give criticisms in a constructive manner.
Avoid gossips, whether listening or commenting about rumors. If you can separate your private life from your professional one, then all the better.
Make sure that you stay focused on your job. Try to learn more about your tasks and go beyond that as well.