It's really up to you, however, keep in mind that the video remains on your profile until you change it. This means, if you later apply to another role, you might want to rerecord the video.

Here are some ideas what to include in the short video introduction:

- introduce yourself briefly (name, previous role, location)

- explain why you are looking for a new job

- mention what you hope to find in your dream position

You only have 30 seconds for doing to, so be concise!

Good luck with your application!