There are loads of reasons to be a regular writer. Writing regularly makes you a stronger writer. Writing regularly makes you a more focused writer. It helps with memory and recall, and with spelling, grammar and punctuation. It can be rewarding. It provides structure. It's brain exercise, and that can only be a good thing.
Trouble is, it's not always easy to get into the swing of regular writing. I've struggled with it in the past, and I still do. We all have down-times. Things happen in everyday life that are our of our control, and sometimes writing is simply impossible. Once you fall out of your stride, it's damn hard getting back into it.
But there are things you can do to ease you into a writing life. And if you plan to have a writing career, you really can't afford not to write regularly.
A lot of people write either to a word count or a set time per day.
Start small, aim for something reasonable like 250 words per day. Young adult author Holly Black breaks down how she wrote her bestselling YA novel (part three in a trilogy) Black Heart here. In her post, she shows her daily word count for the four months it took her to write the book. Most are quite modest—sometimes she writes 300-400 words a day, but she writes regularly and so she's able to finish a first draft efficiently. A lot of people aim for more than 250-500 words per day. If you can manage 1000 words, in two months you'll have a novel. I know, it sounds easy when put like that, but often it's far from easy. It's not impossible though.
There are a couple of extra things you can try if you're finding it hard to write daily:
First, figure out your optimal time to write. Some people are morning brains, and some are evening brains. There will probably be a time of day when you're more productive—the creativity flows much quicker and more fluidly. Experiment. See what feels comfortable. You might also find that there's no real optimal time, and even snagging an hour or two here or there is difficult. But if you really want to be a regular writer, you'll find time. You'll steal it. You'll catch it in a dark alley and beat it up until it works with you.
Second, you need to find your Cave. This can be literal or figurative. My Cave is really my MacBook—as long as I have it, I can generally sink into my stories and get lost. If there are noises around me that I can't ignore, I'll plug in my headphones and listen to instrumental music. Or just plug in the headphones and not listen to anything (those little earbuds are great for noise reduction). But if you need a physical Cave, try to find a space where you're comfortable to write. It doesn't have to be a silent, candlelit room in a secluded Buddhist monastery high in the mountains of Tibet or anything—a lot of people love writing in busy coffee shops, or with the TV blaring background noise behind them—but it does need to be somewhere you can get lost in your ideas and story. If there are distractions at home, try taking your writing elsewhere. Pop out for half an hour and write on a park bench, or at an internet cafe, a library, a bar, at a friend's house, wherever. I've known so many people who sneak daily writing in at their non creative-writing day job (naughty! But awesome!).
And sometimes it's just really hard to start your daily word crunch.
There's a fantastic exercise in The Artist's Way by Julia Cameron called 'The Morning Pages'. This is where you write three hand-written pages, every morning just after you wake up, of literally anything that tumbles out of your brain. It doesn't have to be fiction. It doesn't have to make sense. It should be stream-of-consciousness. You can write about what annoyed you at work the day before, or your reaction to a stupid comment you read online last week. You can imagine the last thing you ate and describe all the flavours and textures you remember. Write a list of chores and how you'll go about them. Write about how irritating it is to have to get up and write three pages every morning. You just write those three pages. They're just for you, not for anyone else. It clears your mind of all the crap you carry around with you throughout the day. Julia Cameron says: ' The morning pages are the primary tool of creative recovery.' It won't work for everyone, but it might for some.
Personally, I think the most important factor that keeps me on track with writing regularly is having an idea or set of characters that I love to bits. I must love my idea and my characters so much that to spend a day apart from them causes me angst and jitters. If you don't love your idea, you probably won't love the time you need to dedicate to it to getting it finished.
This is very long-winded, but I know what it's like to want to write so desperately and then talk myself out of it for some reason or another (self-doubt, time management, tiredness, Skyrim, etc.). When I'm in the groove, there's nothing like it. Productivity and creative movement feels great.
And I think writers should be able to feel great every single day. :)