I think the first step is understanding the real concept of specificity. The idea of mimicking an activity as a way to train for it is not necessarily the best approach. There may be a place for that, but it's only part of the picture.
I would say that most of your training for 2-4 months leading up to ski season should be "ski-specific", but ski-specific doesn't mean mimicking skiing: it means building your body up to be ready for what you will ask of it on the slopes. This means getting strong (not just in the legs!), getting powerful, addressing range of motion limitations and muscle activation shortcomings, and working on cardiorespiratory conditioning.
What do you do in your training now?