Exporting video with FCP 3.x

2. To export your edited footage, select File > Print to Video
Press the Capture/Export button on Director's Cut to set the unit to export. The various export options are described in more detail in the FCP user's guide.

Once you press OK, Final Cut will display a dialog asking you to prepare your device for recording (which should be done by now). Simply press 'OK' to start exporting.