Learn music theory. It's best to learn from someone who knows about writing music. You could google it, or use this link to Wikipedia. Stop thinking about writing a song, and start writing songs. You really want to be a rock star,and rock out on stage like Hannah Montana or Brittany Altman don't you? You daydream about being on stage and hearing the roar of the crowd. Only trouble is, gee whiz, you're dreaming your life away. If you want to write a really good song, you're going to have to work for it. Start today.
Think of a subject you want to write about. Whether it's a song about a break-up, or partying, keep the song focused on that subject. It will make it easier!
Listen actively to a lot of music. Good writers read books. Good songwriters listen to songs. As you listen, think about what you like about a song. Are the lyrics unique? Do the song's chord changes perfectly capture a mood? Do you like the transition from one part of the song to another?
Get technical. You don't have to have a degree in music theory to write a good song, but you should have an understanding of how songs are built. There are infinite ways to structure a song, but there's a common sequence found in most of them (see Tips). As you listen to songs, try to identify the different parts. Check yourself by looking at lyrics online or in a music book; the parts of songs are often labeled in these media.
Be ready when inspiration comes calling. Unfortunately, inspiration usually doesn't strike at the most convenient times, so it's important that you be able to remember each new song that pops into your head, no matter where you are. Carry a pen and paper with you wherever you go, or better yet, carry a tape recorder or digital audio recorder. Melodies can be extremely difficult to capture on paper unless you have a strong music background.
It would be helpful if you have a musical instrument (e.g. Piano, keyboard, guitar, etc.) so that you can explore the music. An added advantage is that you can easily write down the notes (or tabs) when you've got your tune. Figure out what you've got. Once in a while, inspiration will hit you like a full force gale, and suddenly you've got a full song out of nowhere. Most of the time, however, just a small piece of a potential song will come to you, leaving you to do the hard, but fun work of fleshing it out. You should have a feel for what part of the song you've come up with.
If it's super catchy (either a lyrical phrase or a snippet of music), and you can envision it being a repeated theme in the song, you've got the chorusthe climax or summary of your musical storyand you need to write verses to tell the story.
If what you've come up with seems more narrative lyrically or subtler musically a part of a story rather than the main idea you've probably got a verse, and you'll need to write the rest of the story (more verses) and, usually, a chorus.
Set the mood. Make sure your music fits the story. If it's a sad song, you may want your melody to evoke sadness (by slowing it down or adding some minor chords, for example) or you might want to add a twist and combine sad lyrics to upbeat music in order to create a sense of tension and ambiguity.
Say something. A song can get by with poor lyrics, but you've got a better chance of writing a really good song if your lyrics are great. This doesn't mean they have to be serious, but they should not be clich or ho-hum. Write your lyrics as though you're talking to somebody who you want to impress or to someone toward whom you feel some sort of deep emotion.
Make your words sing. Lyrics can appeal to emotions, but they should also appeal to the ear. Rhyming is the most obvious way to accomplish this, and there are a number of rhyme schemes you can employ (see "Tips"). Learn about these and other tools of poetry, and try putting them to work for you.
Strike a balance between repetition and variety. Repetition is what makes a song catchy; repeated choruses, for example, stick in our heads even when the rest of a song doesn't. That's why so many people know just a few lines of so many songs. While there are good songs that are so simple that they have no chorus and have the same line length, the same rhyme schemes, and the same chord progressions repeated throughout them, most people get bored with that. The most common way to add variety is to insert a "bridge" into your song.
Look for the hook. The hook is that elusive part of a great song that captures your very soul and makes you want to listen to that song over and over. Hooks are frequently found in the chorus and often become the title of the song. Sadly, there's no recipe for hooks, but you'll know when you have one. Better yet, your friends will tell you, because it's the part of a song they can't seem to get out of their head.
Smooth the rough edges. If the pieces don't fit together, try building a transition. Put all the sections of your song in the same key. If there's a sudden change in tempo (speed) between the two parts, try gradually changing the speed as you enter and exit the section that doesn't fit with the rest of the song. Try adding a short instrumental interlude that will carry you from one part to the next. Ultimately, if you find it ridiculously difficult to smooth the edges, the reason could be that those two parts just shouldn't be in the same song.
Get feedback. Play and/or sing your song for people and get their opinions. You'll probably get a better idea of what they really think after you've written a few songs: friends and family may tell you that your first song is great even if it's awful, but as they hear more of your songs, they'll probably give you hints like, "It's good, but I liked that first one you wrote better" or "Wow, that's the best song you've written" and "That's a really good song!"
Once you've finished your first song, don't stop. Keep writing and practicing, and you'll find yourself getting better and better. You may need to write a lot of songs before you hit on one you really like, and even after that, you may need to write a lot more before you get another good one. Work hard and have fun doing it!
- Clear Absence