Rules can be broken. But need to know rules before you can.Can break to get some effect, do for a reason.Know the parts of a songs structure and the purpose of each.CH, Verse, Bridge, Solo, intro, development, intro, outro, etc.Take several favorite songs and listen only for structure. Will start to see patterns.Rules such as rhythm melody, structure, tension and resolution serve to give a foundation to ground the song. Can break some rules and balance and ground by enforcing others.If go off in one area need to balance in others. If break all rules becomes anarchy, if break none than can be predictable or boring.HOOK – Mozart, Beethoven, Jackson, Ozzy etc. all use memorable melodic hook. Something the ear can grab on to, that moves song from one place to another, and tells the story. Not just notes in the key, or runs up and down scales. Even jazz improv starts with a melodic motive then develops from there.All music and life are cycles that progress between various states of Tension and resolution. Science, nature, breathing, music is just an expression of already existing principles of life and the universe.If you play Mozart for an animal it will calm them down, if you play Stravinsky or Bartok they will probably become rambunctious or uneasy. The shows how certain dissonance of rhythms and frequencies simply express tensions and resolutions in the world. You must keep this in mind and use that to express the story of the lyric. As well as use to simply progress the flow from one part to the next, one note to the next, one beat to the next, one progression cycle to the next. Ex V-I progression. The principles hold for everything at the micro as well as macrocosmic level just like atoms and galaxies have the same types of cycles and properties. Some would call science and physics, the religious would call God, and others may call it being in sync with Zen and chi.You want to draw the listener in but change before they get bored but not be so erratic that you loose them. Balance.4 track to put ideas down before pay money going into studio. Don’t go into studio without having a well-formed idea of what you plan on doing on how you plan on getting it done.Need to play instrument and know theory, including progression and use of tension and resolution, and how melodies relate to the harmonic structure and movement. If you know that, you will always to be able to write melodies that “work” instead of just being at the mercy of potential inspiration.When in doubt, cut it out. Used in film editing as well as literature and songwriting. Do what’s best for the song as a whole. Even if a part is really cool and you love it. For every part and think you add, ask yourself, “does this add anything to make the song better”.