The best cure for 'writer's block' is a publisher's deadline, so I don't think most professional writers suffer from this problem. When you earn a living from writing full-time, you simply cannot afford to stop writing for long. If you are not fortunate enough to have a publisher's deadline, help yourself by setting your own goals and deadlines. But hopefully you will enjoy writing so much that you will never experience writer's block.
The Best Time to Write
There are no rules governing the writing day. Some writers are well disciplined, others write when the mood takes them. It is important to discover what suits you best. I'm very happy to be brought breakfast in bed while I'm writing. Ruth Rendell's advice on this cannot be bettered. 'Find your own time and place. How many words a day? I don't know.'
Write About What You Know
It is a common adage to write about what you know. That advice is limiting, even stultifying. A more useful precept might be to write about what you find interesting. I've never committed murder but am fascinated by the psyche of people who kill. If I needed to shoot someone before I could write about the experience, I would have been locked up a long time ago. As a writer you are blessed with empathy and imagination. Use them.
One piece of advice I give to aspiring writers is to guard against falling in love with your own prose. This is, perhaps, especially important for crime writers, as the genre is plot driven. With readers keen to find out what happens next, our job is to tell the story. Of course you must always tell your stories as well as you can, expressing yourself as elegantly as possible, but remember that readers want to be lost in the narrative, not lost in admiration of your clever verbiage.
Ionesco said, 'A writer never has a vacation. For a writer, life consists of writing or thinking about writing.' Some people feel they have no choice and certainly, once you commit yourself to writing, it becomes, as William McIlvanney says, 'an inexplicable compulsion.' So choose to write something you are going to enjoy writing. I have never had any desire to suffer for my art. Writing should be a joyful experience. If you do not love every minute of it, find something else to do.
Having a Story
F Scott Fitzgerald said, 'You don't write because you want to say something, you write because you have something to say.' If you don't have a story that you feel you need to tell, forget about writing until a story arrives in your head. You cannot force inspiration.
There are rare authors who write a few words each day that they never subsequently change. Like most writers, I tend to write and rewrite and rewrite. This is where deadlines become so important. Without them, a writer like me could go on interminably tweaking and honing my prose. Sometimes it is necessary to cut quite drastically. George Orwell expressed it perfectly when he said, 'If it is possible to cut a word out, always cut it out.'
The Importance of an Editor
If you are fortunate enough to have secured a traditional publishing deal, your publisher will place you with the best editor for your work, someone who is not only experienced and talented, but who knows the market and understands what works. The right editor is the key to you producing the best book you possibly can. If you have to arrange this yourself, spend time researching and considering your choice of editor. Most of the top editors are working with publishing houses and do not have time to freelance, but choose the best you can find from those available, even if it costs more than you would like to pay. Look at who else they have worked with, and see who has acknowledged their help.
Do Your Research
When writing, you may have to do a lot of research both on and off line. I have never handled a gun. I researched as far as I could on the internet for one of my forthcoming books. Yet in my first draft, I had a small hand pistol cause an entry wound that could only be caused by a Waterloo era rifle, or even earlier period flintlock type pistol. It made a difference of about a centimetre in the diameter of the wound. There was no way I could have corrected that kind of technical detail without expert advice. So I always seek confirmation or guidance from people who really know the field, whether it be DNA, firearms, drowning, police procedure on other continents, or what it's like to work in a market. Whatever you are writing about, do as much research as you can on the internet, but always check your information with experts. You may not know the right answer to your queries, but you can be sure some of your readers will.
Whatever help and guidance you receive along the way, never forget that you are the writer. Above all else, trust yourself.