Balance is the key building block for cross country skiing, and this is an excellent video on how to get started with some balance drills. It is interesting that this is an alpine ski video, but the fundamentals are the same for all snow sports.
Once you master these then:
It is not rocket science and it does not take exceedingly long to master these movements. Once you get them down you can try them with your eyes closed for some added difficulty and you will be ready to glide down the trails with ease this winter.
