As you may have found out yourself, there is no "recipe" for how to become a film composer, but it usually boils down to the following: Become a film composer by composing music for films.
That might sound too simple, but think about it. There are numerous people with daytime jobs who want to become composers. What keeps them from composing? Their daytime jobs. People may be forced to give up their dreams because of financial pressure. That is very understandable. However, it doesn't make you a film composer. Even if you work within the music business, say as a music editor, it won't make you a film composer. Composing music for films will.
As a general rule, network with filmmakers, not with other composers. Make as many contacts as you can, and keep them active.
Having said all that: There are some composers who have started out assisting other composers, thereby learning a lot through their employers' experiences. They have "paid their dues", including (in some instances) making coffee, washing other people's cars, and cleaning up after the composer's dog. The key is to do all those activities with a smile on your face, knowing that, eventually, they might lead to some composing work. There's always a risk, of course, that they never will.
When starting out, expect to work for either
1. credit but no money, or
2. money but no credit (when working as a ghostwriter).
It is up to you to decide what kind of sacrifice you are willing to make, and for how long.
Don't let people tell you that you're not done yet "paying your dues". They may be right. In most cases, they are not. Some composers achieve success after decades of assisting other composers. On rare occasions, a completely unknown composer will shoot to scoring stardom. There is a lot of room between those two extremes. While there are many things in the business which cannot be controlled, a lot of it is about you making your own rules as you go.
Even if you don't have a job as a composer, compose. Be productive. Work on your craft. Find your own stylistic voice. That's a key element. (However: Be aware that sometimes, composers are hired because they can write in the style of another composer but only cost a fraction of what that other composer would charge.) Do something that has to do with composing every day. Write every musical idea down.
Familiarize yourself with the technical aspects of film scoring: synchronization, click tracks, effects plug-ins, etc. as well as the business side: music budgets, PRO's, musician's fees, etc. Own several samplers loaded with the coolest samples. Be prepared to deal with exotic video frame rates and something called pullup/pulldown.
Do not do any work for free (except for charity)! If you do not charge for your work, people will start taking advantage of you. Do not sign away your Writer's Share!
Recognize the fact that there are far more composers than new projects. Then ignore it. Don't waste precious time worrying and whining.
Know that even though there are some notable and welcome exceptions, most people in the industry do not care about the quality of your music. They do not care about how many people cried because of its beauty. What they do care about is recognizable credits. In other words, a mediocre score for a well-known feature will open more doors for you than the best music ever for an obscure independent short film. Again, don't let that discourage you. Ignore it. Do your best work on every project!
Promote yourself. Let business contacts know what you are up to. Avoid sending out mass emails or "unsolicited" demos. Make an impression as an individual, as yourself - not exclusively through your music. Very few "industry" people actually listen to demos.
As much as we might wish otherwise, most of the criteria about hiring you have to do with you, and not your demos. One hears the following mantra very often in the industry: "People like to work with people they like." Therefore, act professionally, make your clients feel at ease, use humor to your advantage, do your best to fully understand and anticipate your clients' needs.
If you are looking for an agent, be aware that agents are only interested in "hot" clients. When they call a producer, director, or music supervisor, and they say that they are representing you, the last thing they want to hear is, "Who? Never heard of your client".
Tell everybody that you are a composer, and people come to think of you as one.
Here's a great quote from Alan Silvestri: "When somebody asks you if you are ready, you are."
Most importantly, keep a sense of humor.
And last but not least: Living in the Los Angeles area is not mandatory, but strongly recommended.
Greetings.
Edwin
P.S. There are books that will give you more information. A good resource is Jeff Rona's book, The Reel World - Scoring For Pictures, available on his website: The Reel World. Also for a glimpse into the bizarre thinking mechanisms behind the Hollywood corporate system, check out Art Linson's excellent book, What Just Happened?. It might be more useful than all your harmony/counterpoint lessons combined. ;-)
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