It's very hard to assess from a video like this because we can't see what anything is doing above the skis. We can't even tell all that much about what the skis are doing since the camera view is distorted and the view is highly dependent on how your chest is twisted at any given time. If you can get a friend to ski down and then film you as you ski by, we'll be able to give accurate feedback.
That said, it looks like you abruptly twist your skis, then hold them in position until you're ready for your next turn. Your turns are a series of abrupt twist-and -hold moves. It also looks like you fall to the inside of the turn, your skis slide away from you and you have to fight to recover balance (e.g. 00:24). This is further hampered by your hands, which appear to sit by your sides. When your hands move back, your weight moves back, and you become more locked into a turn (which is bad). What you want to create instead is the following:
Constant, gradual turning of the legs. There should never be a moment when the legs stop turning. Right now you make windshield wiper turns which create Z shaped tracks in the snow. Instead you want to create an S shape or linked C shapes. As you ski, think about stretching the turn out over a longer time. Count 1mississippi, 2mississippi, 3mississippi throughout the entire arc (speed this up to a waltz tempo as you make shorter turns, but continue to turn gradually throughout the entire turn). If you've reached the "end" of a turn, you should have already started the next turn. No "dead spots" allowed in your turns anymore.
Balance early on the outside ski. This one will take more work, but is required to truly improve your skiing.
- Go to a wide very easy blue with no traffic.
- Begin to traverse the hill (facing across the hill), ensure you can do a couple of hops on snow, lifting tip and tail off snow at the same time. Doing so proves that you're centered along both skis. If you can't lift tip and tail at the same time, it means you have a stance issue and one or more of your ankle, knee, or hip isn't bending enough (or too much).
- Feel your weight move slightly uphill so you're balanced on the uphill ski (which is the new outside ski).
- Relax your inside leg and start rolling your ankles so your skis start moving on edge. Your skis will automatically begin to turn. You should feel your weight over the outside leg.
- As the turn progresses, keep relaxing the inside leg to increase the amount you're on edge. You should feel your weight over the outside leg.
- Through the end of the turn (after your skis start turning past the fall line), start relaxing the outside leg and lengthening the inside leg. Your weight will start moving back to both legs.
In sum: your legs should be working like you're on a stairmaster: one leg is always lengthening at the same time as the other is shortening. (The leg on the inside of the arc is shortening, and the outside of the turn is lengthening.)
Another way to improve your outside ski balance is to drag both pole baskets, but particularly your outside pole, through the snow. Keep your hands within your field of vision and wide, because anyone can drag their poles in the snow if they drop their hands to their hips. You want to draw a clean arc with your outside hand pole in the snow. For bonus points, check your "drawings" to see how your turn shape is progressing.
A way to check your balance is to tap your inside ski against the snow throughout the turn. If you can't lift it, or if you fall quickly onto the inside ski after lifting, it's a cue that you're not balancing on the outside ski.
A final easy way to improve your outside ski balance is to touch your outside hand to the outside of your outside boot cuff. I don't really like this option since it can introduce other weird movements or balance issues, especially since I can't see you on snow to verify if it's working... but some people like it.
There could be a lot of other things going on - if you can get a friend to film you from a stationary position downhill, we'll have better feedback.
Edited by Metaphor_ - 2/21/16 at 9:58pm