The strength of each beat in the melodic line should determine how you set the lyrics to the music. Look at the relationship of each beat to the next; you may find that you will need to choose a shorter or longer word, depending on the song’s configuration.

This may sound complicated, but it’s really a matter of looking at the beats and checking a thesaurus (or maybe a rhyming dictionary). If you’re trying to figure out how to match words to rhythm, this is really your best bet to having it all come together.

If there’s no cohesion between the music and the lyrics, your song won’t reach its full potential. By matching lyrics and melody, your idea will be communicated more smoothly and with a naturalistic style.

Doing this will give your audience a better feeling for the emotions that inspired you to create the song in the first place. It will give them insight into your intent as a songwriter, and that can be a very powerful thing. Check out this post from Songwriters in Seattle for more information about how to match melodies and lyrics.