One basic thing to do during cold is try to give your body some rest. However, make sure that you have some fresh air supply in your room through an open window being dressed in warm clothes. This is because in a closed room, you will be inhaling the same infected air that you will exhale.
Often during cold you tend to feel dry. Hence it is recommended to keep yourself hydrated by drinking as much water as possible as it is also a good purifier. If cold water seems stinging, you can always have it warm which is comparatively easy to drink during cold.
Since you will be at rest so it is advised to have some light edibles in your diet that you stomach can digest easily. Hence you can have some fruits and steamed vegetables along with hot soup. It is recommended to have water-enriched stuff instead of spicy and processed food stuff.
You should remember that if you are under any kind of stress, there is a possibility of infectious particles invading your body. Hence during cold it is suggested to fully relax yourself by engaging in activities like watching your favourite movies, listening to music and reading some interesting stuff.
If you engage yourself in any activities that may require some kind of mental and physical exertions, it may not let you recover from cold. For this reason, it is suggested to avoid any energy consuming tasks.