Here's the best way to climb a hill while cross-country skiing
The most direct way to take a hill on cross-country skis is to run right up it, using quick strides, small steps, and keeping the upper body fairly erect. Why does an experienced skier seem to do this so effortlessly while a beginner ofter slips and slides back to the bottom in reverse? John Wiggin, director of the Woodstock, Vt., Ski Touring Center, says "the most common mistake beginners make is to lean or reach into the hill, thus getting too much weight forward. This forward body position, now combined with the pull of gravity, will tend to force skis backwards and downhill."
So keep your back erect, use small quick strides, and concentrate on pressing down through the snow, not backwards, as you push off onto your forward ski.
Sometimes the grade becomes so steep that even quick running steps can't make it. Then the herringbone comes into play. Making tracks that resemble that pattern, you angle your ski tips outward, forming a V with your skis. Roll the ankles in to get pressure on your inside edges. Keep your poles behind you, helping to give support as you step forward.
Here again, a straight back is important, for it will help your legs to apply pressure downward and outward, in effect, giving yourself a series of l ittle platforms from which to spring as you climb hill.