Prevention comes down to taking care of yourself
Sure, the flu shot will help you fend off the other major winter illness, but there's no magic trick to preventing a cold. Dr. Amsterdam recommends the typical routine of frequent hand washing and coughing into your elbow. But the best advice is the stuff you don't want to hear: Stop eating so many cheeseburgers, cut down on your beer consumption, and don't stay up really late just to finish one more Game of Thrones episode. A healthy immune system is the best defense.
OK, so you took care of yourself and still caught it. What now?
Your first step to getting better fast is going to depend on all the things already mentioned: making sure you're getting the nutrients and rest your body needs.
There are more specific tips to help you overcome the cold, too:
Drink all the liquids you can, and maybe you can justify a frozen dessert
Avoid coffee, soda, and alcohol, which dehydrate the body (sorry). Opt for water, juice, and decaffeinated tea, which keep you hydrated and help loosen up any congestion issues. That's also why chicken broth-based soup is a standard.
Take it easy when it comes to milk, though. Dairy can make your phlegm thick, and might actually irritate; on the other hand, cold treats can be soothing, like a tasty little ice pack for your throat, so maybe opt for a sorbet or vegan ice cream. For once, you can justify the calories, because you're probably not eating enough when you're sick. Gargling saltwater -- 1/4 to 1/2tsp of salt dissolved in 8oz of warm water -- will do the trick for a sore throat, too. (But it’s not nearly as tasty.)