Please stop talking?

I want to ask how can I tell my little student to stop talking and dont make any noise
in a polite way.
I always say : Don’t speak.
Shut your mouth.
you are a talkative one.

Thanks,
Jungie

‘Shut your mouth’ is NOT considered polite in Western society. ‘Close your mouth’ is a more polite alternative, but even then that is not very polite.

Assuming the phrases are said in a polite manner, these are all considered polite.
Please don’t speak.
Please don’t say anything.
Please stop talking.
Please be quiet.
Please listen.
Please pay attention.
Please don’t talk now.

Thanks a lot my dear.