How did you get your first job in scriptwriting and what was it?
First job, second job, fifteenth job... It's the same process, and in fact it's important to be keeping an eye out for work all the time, even when you're already employed. Here's how I got all my jobs in screenwriting:
Make friends. Be someone people want to play with. I have several different groups of friends and while many of them are writers, many others are actors, directors, producers, development executives, and even people who aren't in the entertainment industry at all. The one thing everyone has in common is that we all know and like each other's work. I refer my friends to jobs, and they refer me; we look out for each other, and applaud each other's success. Life's too short to spend it in petty competition with your colleagues.
Give great notes. Don't be afraid to look stupid -- all you'll end up doing is keeping your great ideas to yourself and no one will know what you can do. I got my first staff job because the head writer asked me to type up his feature film script and give him notes on anything I noticed as I was typing it. My first thought was, what notes could I possibly give this brilliant man, other than pointing out the occasional spelling error? Then I read his script and I realized I did know how to make it better. I gave him three hours worth of notes, and he ended up using most of them -- and he promoted me that afternoon.
Ask for the opportunity to write. The worst that can happen is they'll say no, and at least you'll know where you stand. Never assume you'll get the opportunity to write without asking for it. If they won't let you write, see if they'll let you pitch some ideas or rewrite a few scenes. You want to show you've got talent. When you do get the chance to write, be sure you understand what's expected of you and when it's expected by. Don't blow it by not knowing the deadline was yesterday.
Take classes; learn how to pitch, not just how to write. Getting people excited about your projects is half the battle.
Pay attention to people who are better than you and figure out what they do well, that you don't. For instance, I worked with a guy who was never attached to a single idea. He could come up with ten different ideas on a dime, and if the head writer hated one, he just threw out the next. I deliberately cultivated that talent and just kept at it until I became really good at churning out ideas and not getting defensive when someone didn't like them.
Say no to projects that you don't like. If you don't understand something, if it doesn't speak to you, it's a waste of everyone's time for you to be on board. This is especially true in the vast number of "spec" projects you'll be offered -- projects with little or no pay, or deferred payment.
Say yes to projects you love, even when there's no money attached. My two big successes this year are a children's series I've just sold to a major animation house and an independent movie that will be shot next month. Both I did for no money up front because I connected instantly with the projects. If you're passionate about something, do it; if nothing else, you'll have the joy of working on something you love.