Keep your head cool and do not over-react to the harassment, as that is exactly what the other person wants you to do. By remaining calm, you will not be giving the harasser the satisfaction that he is getting to you and making you feel uncomfortable. This will force him to either rethink his strategy to harass you, or will make him give up.
If the harassment is causing you a lot of discomfort and you can feel yourself to be nearing the tipping point, put your foot down, stare right in the eyes of the person harassing you, extend the palm of your hand forward just as a traffic policeman signals “Stop” and utter the same words to your harasser. Let him know that you are in no mood for enduring his nonsense.
Ask yourself why you are being harassed? Is it because of a particular habit that you have or some action that you may have done in the recent past to attract the attention of your workplace bully or bullies. Try talking to the harasser and solving the issue in a civilised manner. They may have misunderstood you, or you may have done something wrong and therefore owe that person an apology.
Remain focused on your work and do not let the harassment distract you from what is really important. You work to earn bread and butter for yourself and your family, which is why you cannot risk putting your job in danger. Do not let your mind think too much about the on-going harassment.
If you are really desperate to make the harassment stop, start giving off an impression that the words and actions of the person harassing you is making you extremely depressed. Start speaking softly and make your body language give off an impression that you are really down. Everyone has a heart and conscience. When the person harassing you notices how worse you have started feeling, his conscience may stop him from continuing and he may even come forward to lift you back up from the depth of your fake depression.
Get assistance if the harassment does not stop. Talk to your colleagues, or take the matter to the management. You are getting paid to work, not to put up with the bullying of your co-workers.