A section’s melody is one of the most important elements of a song—as well as one of the most difficult. There are several ways to approach writing a melody, and when we use the same approach, we run the danger of writing similar melodies for every song we write. If you are looking for some fresh ideas, try this exercise.
1. Start with a new melody
Many of us write melodies by intuitively humming a tune, feeling around for it. Some of us need a chord progression in the background. Either way, begin with how you normally start writing melodies. Keep it simple, no more than 2-4 bars.
2. Interpret that melody
Even if you are not familiar with music theory, there is a simple way to understand what your melody is doing. You don’t need to know the notes, just consider the direction. Possible examples include:
Ascending

Descending

Up then down

Down then up

Staying in place

Your melodies could be more complicated than that, and that’s okay. You can draw the shape of your melody in your mind.
3. Do the exact opposite
Now that you know what your melody is doing, sing the same melody but the opposite way. If your melody was ascending, you will probably have to start on the last note to now descend. Play around with the directions.
4. Determine which melody fits your section better
Many times if our melody is ascending in the Verse, we descend in the Chorus to create contrast. Sing your two melodies side-by-side; which melody sounds like a Chorus? Which sounds like a Verse? A Pre-Chorus?
This is a simple exercise which gets more complicated the longer your melodic pattern is. Try longer melodic patterns where an entire section is a continuous melody. Try a call-and-response by opposing your melodies one after the other within one section. Maybe even try placing a little surprise in your melody!