Steve Barnett tried to convince me that step turning is an essential technique for negotiating very tight trees, but I'm short and squat and heavy and my legs and steps are too short for my long skis in deep snow LOL; but really, stepping out, turning the ski while doing so, and coming down on a ski perpendicular to the slope, then bringing along the other ski can be very effective.
But what I was talking about is (1) steering: having taken some weight off the ski, start turning it the direction you want it to go using your lower leg, not initially relying on ski sidecut or flex;
(2) angulating: what the old instructions called "big toe, little toe"; your downhill ski is tipped/weighted using the inside of your foot (big toe) and your uphill ski is weighted/tipped using the outside of your foot (little toe).
But more effectively, as the DesLauriers brothers recommend for alpine skiing, at the end of a turn, unweight both skis, drift into the fall line, then full unweight the previously downhill ski (to be your uphill ski), even to the point of lifting it up slighty in deeper/grabbier snow, tilting you ankle/lower leg so the outside edge of that ski is down, the inside edge up, and if necessary move it parallel to th the now automatically weighted and tipped to the inside (angulated) previously uphill ski. Now the once downhill ski will be your uphill ski. On modern alpine skis, this is done so quickly and easily and the timing slightly altered so as to result in skis that appear to never stop carving (at least on groomed snow).
To make it more clear: (1) you have just made a left hand turn (or just about to start skiing downhill when your right ski is downhill & parallel to the slope).
(2) You lightly unweight both skis (sometimes even with a vigorous up pull if the snow is deep), such that they turn into the fall line.
(3) Simultaneously steer both skis towards the right, while totally unweighting your right ski, flexing your lower leg inward (moves the inner edge up) and, if necessary, moving it parallel and adjacent to your left (downhill) ski. Initially, you may even find yourself moving the new uphill (right) ski slightly forward, above, and uphill of the new downhill (left) ski.
(4) This automatically places your whole body weight on the left (downhill ski), compressing the camber and bending the ski as well as placing it on its inner (uphill) edge.
(5) Then pressure both skis through the turn with down weighting (pushing down with your legs). This is a simple parallel turn.
(6) If you wish to make a tele turn: (a) as you unweight and tilt the right ski slide it slighly back such that when you drop into the tele postion your right knee is almost to up against the back of your left knee/calf/ankle depending on how deep you want to drop; (b) both skis are angulated, weighted, flexing, and parallel.
(7) In the tele turn, you should feel like you are weighting the rear ski through the turn more than the lead (downhill ski)--that will be an illusion because the pressure on you downhill will actually be great/greater practically no matter what you do.
(8) A XC downhill turn, IIRC, is similar, but, after initial steering, often with a more vigorous stepping/weight shift to the downhill ski with a more active movement of the uphill ski parallel to the downhill ski before downweighting. This greater stepping/steering/stem christie like action is often desirable with high cambered/double cambered skis with little side cut and a long length. A tele turn on long, skinny XC skis may require dropping your knee much farther back such that the the tip of the rear is closer to the boot on the lead ski, with an angle between the 2 skis that creates an arc that assists in turning (with both skis highly angulated).
CAUTION: skiing is a dangerous sport and it is even more dangerous to take advice online; a good PSIA instructor is worth a thousand words; and even one lesson is worth a couple of hundred dollars (you will save so much more in doctor's bills and physical therapy).