What's the best way to shake a cold?
There are various over-the-counter remedies that will help you feel better when you have a cold. But if you simply don't feel up to it, then do not go into work. You will be doing no one any favours if you are in work coughing all over everyone, and not giving your body the chance to recover.
And remember most cold and flu remedies just mask your symptoms. Your body still needs to tackle whatever is causing the illness.