Tony writes: Writers always say "write every day." What if you haven't found an idea you want to stick to and write yet? What do you write about every day then? I really try write every day, but some days I simply don't have any ideas. Do I just need to work through it and squeeze some out of my mind...or find a new profession?
I don't write every day. Maybe I should, but my system seems to be working for me right now. I think the difference between professional writers and aspiring writers, though, is that pros don't wait for inspiration to strike. They can sit down and force themselves to write even when they don't feel like it, even when it's really really hard and Swiffering the kitchen floor would be way more fun. So if you're concerned that you don't have the determination to be a professional writer, make that your test. Can you write even when you don't feel like it? You're going to have to if you want to make writing your livelihood.
I do think that working through your inspirational dry spells is something you get better at with time. I haven't gotten paid to write scripts yet, but I've heard that it's easier to write when you know you're getting paid to do it. From my own experience, I do know that it's easier to write when you know people like managers and producers are waiting to read your material.
There's also more to being a writer than churning out pages. In addition, you should be devouring scripts, shows, movies, etc. If you're having a tough day, catch up on some reading and watching. Watch actively and break down an episode or movie for structure. It's still productive.
I also find it helpful to be working on a couple things at once. If you're stuck - or if you're waiting for notes, jump over to another project. This way, you won't start to hate all of your projects and you'll be able to look at things with a fresh perspective.
If you're having trouble coming up with ideas, think about your favorite shows or movies. What inspires you about them? What things in the world really bother you, or make you want to learn more? Who in your life is an interesting character? What is a story that only you can tell? Being an avid reader of newspapers, magazines, even Craigslist ads might also spark ideas (the feature I'm currently working on is inspired by a CL ad).
Lastly, writing scripts is impossible if you don't have a solid plan/outline/etc. Are you just starting with a blank screen and jumping right into the script? Fill in a SAVE THE CAT beat sheet first. Write a character bio (more on that later). Clarify your theme. I always want to jump into writing the script immediately because I like dialogue best, but you'll save yourself a lot of time and heartache by doing adequate prep.
(And by the way, writing every day is kind of lame. People with more "normal" jobs get weekends...why shouldn't we?)