Watching a Clint Eastwood film just recently - and after all the shooting and all the explosions, Dirty Harry comes out with a line that perfectly sums up how to do well in your career; and in your life; and, even, in selling your book.
A man's got to know his limitations.
It has utterly transformed the way I sell my novels.
So let me spell it out: before you can make any headway with a project, you've got to know your weaknesses.
When you know your weaknesses, you can identify your strengths.
And then you can start playing to them.
What are my strengths? Well I've got a few - but one of the big ones is my kids. Unlike me, they are cute (ish).
Knowing your strengths - and weaknesses - is important for almost any venture you can think of. But in that weird, arcane business of selling your own book, it is absolutely essential.
Today, more books than ever before in history are being published. Thanks to self-publishing, over 10 thousand new books are hitting the shelves every month.
20 years ago, if you'd written a turkey and couldn't find an agent or find a publisher, then you'd just have to go off into some dark pit, lick your wounds, and write a better book.
Not any more though. These days we can all stick two fingers up to the agents and the publishers and - regardless of the quality (or lack of it) of our manuscripts - we can just go off and get the thing printed.
So: a lot of competition out there.
A lot of these writers will have read up on how to sell their books. Tweet! Blog! Suck up to journalists! Schmooze the reviewers! Shower out your books like confetti, and hope and pray that they will eventually end up in front of A Player.
Well... I'm not saying it doesn't work. It might work. But it is probably not going to work - the reason being that there are tens of thousands of other writers out there, all of whom are also screaming and yelling from the roof-tops.
And there you are, a nightingale trying to be heard above this great chorus of seagulls!
So: Tweeting and blogging and schmoozing can all work. Sending your books out... well it can work. But never forget that you are going to be up against some really serious competition - writers who are tweeting and blogging and spending weeks on end doing all things internetty. One writer I know, very successful, is called Robert Twigger. How did he come by his name? Twitter Plus Blogger Equals... Go figure. But Twigger is hungry! There are a lot of hungry writers out there doing their stuff on the internet. They're good at it and they're really, really keen.
But if it's not your strength... and if you don't really feel comfortable tweeting or cold-selling your books in Waterstone's, then what I'd suggest is doing something different.
Analyse your strengths. Start playing to them.
Well I've got a few strengths. I'm a journalist - so I can sniff out stories.
I'm okay with puns.
Ohh... and one more thing. I've got these two sons. And though I'm not saying they're cute, what I AM saying is that they're a lot cuter than me. What... Exploit my kids to sell my books? Is this man completely without shame??
When my first love story came out seven years ago, a friend of mind, Tim Maguire, made a video to help plug the thing. The book was called The Well-Tempered Clavier, (lousy title; tell me about it) and I was looking soulfully at the camera as I mumbled on about the book.
But the problem - the big problem - was that author videos are, by definition, incredibly boring. Who wants to see an author yakking on about their book? Even if it's J.K.Rowling or Bernard Cornwell, it's still pretty tedious stuff.
So: a few years later, I had my next love story out. MUCH better title - The Woman Who Made Men Cry. Don't you just love the sound of that woman? Doesn't she just sound like a heart-breaker?
And this time, along with all the bloggin' 'n' the tweetin', I decided to make another video.
But a very, very different kind of author video. The sort of author video that no-one had ever seen before.
Work out your weaknesses. Analyse your strengths. Apply them.
First of all: I wasn't going to be the star. I couldn't be the star - I'm not cute!
But the kids on the other hand... well, they're not too bad.
And as it turned out... the video was hilarious. Even tenth time round, I still find it funny. Painful. But funny.
Anyway - here's a pledge. If you DON'T laugh, then drop me a line. I'll send a book to the first 100 curmudgeons who fail to be amused. Free. Gratis. And for nothing.
Well - after that video, I had truly seen the light.
With my most excellent friend Ross, I started churning out more and more of these slap-stick videos, all of them in the same vein.
Author tries to plug his book; kids cock it up; author gets bashed/humiliated.
Simple - yet effective.
And then when the latest love story came out - The Woman Who Was The Desert Dream (not quite as good a title as The Woman Who Made Men Cry, but just about passes muster) - we did it AGAIN!
So I'm not saying that funny videos are the way forward for any up-and-coming author. And I'm not saying that you shouldn't be blogging and twiggering and plundering the internet for all you're worth.
But what I know is that if you're not good at it, and if you're heart's not in it, then it is going to be a hell of an uphill struggle. You'll always be going against the grain - because you'll be competing against authors who love it and who are very, very good at tweeting and blogging.
Though that's not a problem. It's just a weakness. And you know it.
So now you can analyse what your strengths are. And start playing to them.
If you're a charmer, good with people, then you should be meeting people in person. Don't waste your time on e-mails. Schmooze the book-shop owners and the festival directors in person.
If poetry is your thing, then start tweeting in haikus.
If you are funny, then find yourself a vehicle to start making people laugh.
Look: anyone who tells you that there is some magic bullet out there which will turn your book into a bestseller is a complete and utter charlatan. There isn't. There are so many new books out there that even a lot of really good books are sinking without trace.
Which means you've got to be much more clever when it comes to selling your book. It's no good just doing what every other author is doing. Blogging and tweeting may have shifted a ton of books ten years ago - but that bandwagon has now well and truly disappeared over the horizon.
The only thing that is really going to sell your book (brilliant writing excepted) is a clever, quirky idea that is... FRESH. New!
And you're the one to work out what it is.
Like Clint says: know your limitations. Work out your strengths. Apply them.