Details:
To select an interface language and theme (skin) for your control panel:
1 On your Home page, click the Interface Preferences in the "Acount" group.
2 Select the desired interface language and skin from the respective drop-down
boxes.
Plesk‘s interface has been translated to a number of languages, so if you do not
see your own language in the list, ask your provider to install the respective
language pack.
3 Click OK.