Fundamentally, your question was where to start. The place to start is to look at videos Harald has posted on line, and videos by PMTS skiers in the Movement Analysis section, and ask yourself if you would like to ski like that. If you want to ski like that, it won't come from a few tips to pick up to incorporate into your everyday skiing. It will take a lot of work to wire all these new movements together.
I would recommend getting the Essentials book to really understand the PMTS terminology regarding the primary movements. If you like the elegant skiing you see in the online videos, Essentials will really help you understand how all the different Primary Movements are complementary and what a beautiful system PMTS is, through incorporating such a thorough biomechanical understanding. In order to incorporate PMTS into your skiing, I would recommend you follow the progressions in Expert Skier 1, then 2. Essentials will really help you understand what you are working toward through Expert Skier 1 and 2.
One of the most important things that will come out of starting with Expert Skier 1 is to understand the importance of proper alignment and bootfitting. You will see an immediate benefit in your skiing from being properly aligned. If you really want to incorporate PMTS into your skiing, you will benefit immensely from lateral boots, which might not be what you are using now. A fitting from a PMTS bootfitter is a game changer.
Sometimes you just have to get away from the gang and practice on your own.
- Skip a run with them to work on a few drills.
- Work on a few drills during part of the run where terrain and traffic will allow.
- Have a list with you of some things you want to work on every time out - even when you are free skiing.
When you really feel the difference that PMTS makes, and you really understand the movements, you will start to become passionate about doing drills.
Switching back and forth from PMTS to the way you are used to skiing will slow the rate at which you incorporate PMTS into your skiing. Going to a PMTS camp is the best way to take a "time out" to start to rebuild your skiing.
If you look at the Movement Analysis section of the forum, you will see examples of real PMTS skiers posting their video for commentary. You will see a wide range of skill levels. Not a whole lot of skiing posted there which is not groomed. In part, that is because the skills (and flaws) which translate into the ability (or limitations) for skiing off-piste are all there to see on the groomers. And PMTS skiers know that the place to fix those flaws is on the groomers before those skills can translate into bumps, powder, off-piste.
Erik