You boot into single user mode by holding command-s at startup. From there you could get access to your drive by typing mount-uw / and navigating to where the installed files were and deleting them (it's a bit risky if you don't know what you're doing because you are running as root).
You can also supposedly reach a console mode by typing >console at the login window. I've never tried this myself but it would let you get a fullscreen terminal with the system components fully loaded. To leave just type exit and a normal login should restore the GUI.
If you have just installed a kernel extension, boot holding shift to get into safe mode with a GUI and try to fix it that way.
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You can also supposedly reach a console mode by typing >console at the login window. I've never tried this myself but it would let you get a fullscreen terminal with the system components fully loaded. To leave just type exit and a normal login should restore the GUI.
If you have just installed a kernel extension, boot holding shift to get into safe mode with a GUI and try to fix it that way.