1. Write in the treble clef on the upper stave and the bass clef on the lower stave. Insert a necessary key signature of the hymn and write in the meter signature.
2. Notate a melody on the upper stave with the stems up. This will be the soprano voice of your harmonization.
3. Determine the key of the hymn. Look at the key signature and the last note of the tune. The melody normally ends on a tonic note (1st, 3rd, or 5th scale degree of the home key).
4. Find the caesura point (the breathing place) and notate it with a "v" sign. Usually it is located after first four measures.
5. Determine what the most suitable chords are for each beat in the melody. Choose from the 3 most important chords: Tonic (a triad or a 3-note chord built on the 1st scale degree), Subdominant (a triad built on the 4th scale degree) or Dominant (a triad built on the 5th scale degree). If you know other chords, you can choose from them as well.
6. On the lower stave write in the bass line based on these chords with the stems down. You can make the bass line a bit smoother by using 1st inversion chords. Aim for the contrary motion with the soprano line most of the time.
7. Write in the 2 missing middle parts: alto (in the treble clef with stems down) and tenor (in the bass clef with stems up). Observe the proper voice leading: let the common notes of the chords be stationary and other notes move by a step.
Another way to connect two chords is in contrary motion with the bass. Here the voices move to the closest notes of the next chord. Avoid voice crossing, intervals of two consecutive unisons, 5ths and 8ves and forming a 5th or an 8ve parallel motion from the previous chord. The largest interval between the 3 upper parts is the octave while the distance between the bass and tenor could be one and a half octave.
Use the above steps to harmonize your favorite hymn today. Once the harmonization is complete, remember to play it on the keyboard, piano or organ. Correct any mistakes you find along the way. You can also impress your friends or family by playing your hymn harmonization for them.
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