Thirty seconds is enough for roughly 65–80 spoken words. Trying to fit five ideas into that space forces you to rush. A strong short video makes one useful change in the viewer's mind.
Open with a specific tension
Name the problem, mistake or surprising contrast in the first sentence. Skip greetings and biography. The viewer should know immediately why the next line matters.
Give one idea with one example
Explain the principle in plain language, then make it concrete. An example turns advice from an opinion into something the viewer can use today.
End with the next action
Tell the viewer what to try, notice or change. A useful ending can be a tiny assignment; it does not have to be a sales call to action.