Clear styles from pasted text

I am working on some documentation thing. There’s plenty of text to copy and paste into my diagram. Most of this text carries formatting that I don’t want, like font or background color. I just don’t seem to find any way to have OmniGraffle either ignore it or clear it after pasting. How do I get this done?

The command you’re looking for is called “Paste and Match Style”. Some people prefer this behavior over standard Paste and go so far as to remap the shortcut it in the Keyboard pane of System Preferences.