Titanic will never be the same without the soundtrack. Often, background music makes or breaks a movie. It is hence vital to pay a lot of attention on the sound effects and theme songs.
 

• Start with the melody and the chords - if your melody doesn't get you humming, or make you feel, you're kidding yourself if you think your words are going to save it.

• Remember that the theme song has to suit the movie title, the mood, the pace, the image. For example, don't ever have a slow song for a comedy.

• There's nothing wrong with writing something that sounds like something you've done before. Maybe the thing you're working on now will be the hit, and the old song will be forever left on the shelf. Just free yourself to write anything that sounds good.

• Do not change your style of writing  just because people tell you it sucks or that it's too cliche. Look at Beck. You hear so many writers that used to be good turn into old hacks cause they get bored with writing good catchy songs. If you have the knack of writing stuff that gets people singing, stick with it and screw those urges to 'go jazz'.

• Be realisitic, don't be too sentimental. Trash songs you know you will never want to hear it again. Do not think that everything you write is a masterpiece. It takes time and effort to compose a good theme song

• It will be a great help if you can read the script and understand the plot of the story. Watching action movies without the fast paced music will seem REALLY weird.

• Practice often. Write at least three times a week, so that when work really comes you are as smooth as a beer. Just write a song about anything. You can put meaningful lyrics to it later. You need to get your brain out of the habit of thinking it needs inspiration or special conditions. Train it.

• When you are feeling down, or maybe you are really estatic about something, write a song, or maybe write out how you feel (you can use them as lyrics later). Write from your heart. True feelings can give really sincere and great ideas. Sincere lyrics move listeners' hearts too.

• However, never force yourself to squeeze out something. It usually turns out crappy. Take a walk in the park, listen to the radio, or even go on a trip to find new inspirations.

• The lyrics do not have to rhyme EVERYLINE, but it will be catchy if you can. The rhythm must go with the lyrics too. Jerky lyrics will be a pain to the ear.

• Do not despair when you have a writer's block. Take a break. Never give up.

• Listen to veterans' advice. They usually come in handy.

• Go back to your previously kept works. Rewrite them, improve on them. Keep doing that, and in time to come you will have a gem that has been polished.

• NEVER think of the money you will get from writing. Being mercenary will blind your eyes, and songs that come out will sound be commercialized and packaged.

• The song should have a strong start, a progression, express the desired effect in the scene of the movie.

• The lyrics should be kept simple and clear, so that listeners can understand easily.