My skin is always dry and is a challenge to take care of during the winter.  Another major area I forget to take care of are my legs!  It's easier to skip shaving during the Winter. 

My hair is wild & wacky at the best of times but it seems to really play up even more so in the winter with the cold air, I now try to deep condition a little more than I normally do.

Also, while I have crazy oily skin on my t-zone etc, my hands during the winter get so so dry, if I forget to look after them they even crack and become sore! It is important to rember to moisturise the hands too!

I find that the most challlenging during the winter is dry skin. I am constantly puting lotion on and chap stick on my lips.