Since long skis are harder to control and learn with, it is recommended to get slightly shorter than average skis. Most people will tell you that your skis should be as tall as your chin. However, try out skis that are as tall as your collarbone. Longer skis are more stable at high speeds and will give you more float in deep snow-like powder. But as a beginner, you should not do any of those things. That’s why a shorter pair of skis makes much more sense.
The only drawback to this is that you will eventually want a longer pair of skis. For that reason, you can buy your first pair of skis used to save money and eventually buy longer ones. Once you’ve gotten past the beginner stages, opt for chin length.