A month ago I caught a dreadful cold, the second within only a few weeks.  It was the worst cold I've had for many years.  I'm only now beginning to feel much better, although I still cough and splutter at inappropriate moments.  
Perhaps my resistance is rather low, which is quite understandable for the time of year but there's a lot of winter still to go.  I need to do something about it - and now!

This site has a few ideas: http://myfrugaladventures.com/2014/11/how-to-stay-healthy-this-winter/ and here are some of the main points:

Drink Water!

Do not let this slip! In summer we are always thinking about nice ice cold drinks and staying hydrated. I think this easily slips in winter when I tend to start drinking coffees like it is my job and I forget to be diligent about my water consumption.

You Must Rest.

I have to really force myself to make rest and sleep a priority. In winter we  get so busy with parties and travelling and shopping and the holidays. Don’t let your sleep fall off your priority list this winter and if you do start to feel like you might be coming down with something- the very first thing I do is stop and rest.  It is the best way to keep yourself healthy and help your body fight off nasty stuff.

Stick to Your Fitness Routine.

This is another hard one… it is cold outside maybe snowing or rainy and who wants to put on light clothes and head out to the gym.   If that is the same for you in winter, it might be time to revamp your fitness routine. It is really important to stick to your routine and find a way to stay on track with fitness. Having a fit body is the best way to stay young and energized. I can absolutely feel the fatigue and moodiness when I let my routine slip for a few days.  

 Wash Your Hands.

Seriously wash your hands like you have a slight obsession with it. I try not to be mindless when I wash my hands in winter - remember to thoroughly lather and wash the front and back of your hands for 30 seconds. And do it a lot. (and slather on lots of hand cream afterwards)

Take a Bath

A nice hot bath can be so good for your body, especially if you are feeling a little fatigued. 

Eat Right

In winter it gets so cold and there are just treats and wonderful things everywhere to tempt you. Fresh spinach salad? No thanks, pass the steaming hot bowl of potato soup please! And I’d like to wash that down with a few cookies… and possibly a Hot Toddy.   It is actually so easy to let your diet slip a little in winter and it is so important to continue to fuel your body with the right things to stay fit and energized.

Mind Over Matter.

This might sound silly but I am a firm believer in the power of your own mind.  I really do believe that if you tell yourself you are healthy, happy, energized… whatever… you will start to feel those things.  

That's me!