1. The most important thing I've found so far is the kidney trade on the blackmarket which is lucrative and offers flexible working hours for most aspiring composer/lyricists. Refrain as long as you can from selling your own kidneys, but if worst comes to worst you've always got some money locked away near the small of your back.
I would consider myself an early career theatrical composer & lyricist. That is I've been doing professional work for about 4 - 5 years. That isn't to say I've been able to make my living entirely from my writing work. Even after five years I earn approximately 80-90% of my living through income from writing. I would like to say that's because I live and extravagant and hedonistic lifestyle that could only be accommodated by the sort of salary that was hefted by the Wolf of Wall Street in a week. Unfortunately that is not the case. I live in a small one bedroom flat with my other half in the southern suburbs of London Town. Most of my money goes on rent and baked beans. Even so, it's not such a bad way to be if 4 out of 5 days of the week I spend writing, meeting with creatives and thinking about exciting projects.
I must admit, along with the rest of the people who go into this business, I was under the delusion that show business was big business. And it's true that you can earn a fortune, but it's also true that for a long time (potentially forever) you won't earn a fortune. In fact you'll only earn just enough to get by.
But how do you start getting some in the first place?
1. Work for free. All of my original professional work came from people who I had helped out pro bono previously. Fortunately, what working for free does is get your name in front of people who can potentially give you money for your work. Bonus. Of course you can only do this for so long (but hopefully that's all you'll need to do it for).
2. Work with lots of people. Especially directors, producers and writers. Directors are often hired to direct a play and then have leeway to choose their own creative team. If you are their favourite composer they are likely to choose you (especially if they owe you a favour). Producers are the ones with the money, they are great if you have an original idea of your own that you want to get paid for writing. Go and see Fringe Theatre and look for the name of the producer, search engine and get in touch. Most fringe producers are keen to meet talented young individuals with original ideas. Writers are also important, they often have sway with producers and directors (although they can be left out of the process entirely), but it can't hurt to be in their good books. Tweet writers you like, ask to meet up. Again it can't hurt.
3. Composer/Lyricist jobs are very rarely advertised and the competition for them is intense. Where you do find applications, do your best to make yourself standout from the crowd. Offer to write a bespoke song for an advertised project as a demonstration of your ability and professionalism. If you do a good job, you might just pip the nearest contender. I have managed to get several jobs by offering to write a demo number (a few hours work can lead to a 3 month paid contract).
4. Work in the theatre is about relationships. You don't have to schmooze with people but it is in your interests to be cordial and nice to the people you work with. I'd say 80% of my work comes from people I've worked with before or personal recommendations from people I've worked with before. They might recommend you if they don't get on with you but you do a fantastic job. They'll definitely recommend you if they get on with you AND you do a fantastic job.
5. Be careful and thoughtful about what you want to be. There are many musical jobs in the theatre and often they are complementary, Composer, Musical Director, Rehearsal Pianist, Music Supervisor, Teaching, Chorus Master... etc. One individual may have the talent to do all of these things, which is great, as it means you can earn money doing things you love. However, this multi skilling can come at a price. In an interview Alan Menken (composer of all the brilliant Disney tunes) said that at university he was spending all of his time as a rehearsal pianist or a musical director which meant he didn't have the time or energy to concentrate on the thing he loved the most, composing. As a result he made a decision. Though he had the ability to do all of these other things he made a conscious choice to refuse any further offers of work that were not compositional commissions. As a result he did alot more composing for free than he would have liked and he had to work other jobs unrelated to music sometimes to pay the bills. But the majority of his time and energy was spent honing his compositional craft which eventually ended up with him being one of the most celebrated film and stage composers of recent times. I'm not saying that you should give up these other skills as they can make you usefully employable on projects when someone needs a composer & musical director in one. However, if you want to write songs for a living, you would do well to concentrate your energies on composition and lyrics as much as possible.
That's all my thoughts for now I suppose. After all, it's not about the money. It never was. But you have to be able to afford those baked beans right?