How can I type the “@” symbol via VNC with a PC keyboard? I'm connecting from a PC to a Mac via VNC. Now I want to enter some special characters like @. How can I do that?

This page didn't help. Other keyboard shortcuts I found out:

Alt = cmd

Shift + 7 = _

Shift + - = ?

I'm using a German keyboard, but it seems that the English keyboard layout is used by VNC, because y is z. The clipboard also don't seem to work correctly ...

Edit:

Physical keyboard layout PC:
German keyboard layout “T1” according to DIN 2137-1:2012-06

Logical keyboard layout PC:
German

VNC mapping

Logical keyboard layout Mac:
German

Physical keyboard layout Mac:
German
From the menu bar select System Preferences

Select the Keyboard Icon 

Select the Keyboard tab

Select the "Show Keyboard &amp; Character Viewers in menu bar" check box.

From the menu bar select either the Character or Keyboard viewer.