Connect one end of the MIDI cable to the "MIDI out" port of your keyboard, and connect the other end of the MIDI cable to the "MIDI in" port of your computer. Alternatively, if your keyboard uses USB technology, connect the USB cable from your keyboard's USB port to your computer's USB port.
Turn on your keyboard. Turn on your computer and open your MIDI recording software, such as MultitrackStudio. Press the "Record" button and play a few notes on your keyboard to test that that the connection has been made properly. Press the "Stop" button to stop recording. Press the "Play" button to play back your recording to make sure the connection is complete, and that the software recognizes the device.
Press the "Record" button on your MIDI recording software, and play your keyboard music that you want to record. Press the "Stop" button when finished. Press the "Play" button to listen to your recording. Create a new file and record your keyboard music again if you are not satisfied with your recording.
Save your recording as a MIDI file. Click "File" on your MIDI recording software, and click "Save as" from the drop-down menu. Title your recording and then select the "MIDI" option from the file type drop-down menu. Click the "Save" button to save the MIDI file to your computer.