Getting plenty of rest is extremely important. You need all your strength to fight off a cold.
If you let the mucous build up in your nasal passages, it can fill your respiratory tract and possibly lead to a respiratory infection. However, remember to blow your nose lightly as too much pressure can lead to middle ear infection. And make sure you always wipe your nose with a tissue so you don’t contaminate your hands.
Do not starve a cold. Instead, keep yourself well nourished with a well-balanced diet so that you have enough energy to fight off the virus. Also, many cold remedies can cause an upset stomach if your stomach is empty.
Keep yourself hydrated with water and clear juices to ensure the lining of your nose and throat does not dry out, allowing mucous to remain moist and easy to clear from the nose. Stay away from drinks that contain caffeine or alcohol, both of which lead to dehydration.
Relax in bed, catch up with a good book and eat some warm soup. You may not want to miss work or school, but in the long run, getting better quicker will save you from future absences (and prevent you from infecting others around you).
Change your toothbrush, and your bed sheets and covers after your cold symptoms subside.