Developing balance on the outside ski is paramount and something you should work on as often as possible. Here are some ideas...
As a beginner, try tapping while gliding on a traverse, see On the outside ski. Then progress to keeping it up longer and longer until you ski the entire turn on the outside ski only.
Slope matters, so start on a green and progress to blue and black only as your skiing and balance improve.
As you glide turning, during each turn, pick up the tail of the inside ski and ski the entire turn on the outside ski only.
NOTE - you can drag the poles for balance.
Ideally, you lift the inside ski as the edge of the outside ski engages, so you have a platform to stand on.
Use the upper body to balance: crunch your shoulders over the outside ski. The more weight your lift off the inside ski, the more you have to counterbalance with the upper body over the outside ski).
Here's another video with more details:
More topics:
Some related drills: