These are the key things I've found most helpful - some gleaned from my years working in publishing, some from my experience of writing my book. I hope you find them useful too ...
1. Don’t expect perfection in the beginning.
If you are anything like me, whatever you begin with will probably be dreadful. But that’s OK: you have to start somewhere. Take comfort from Mike Gayle, who approached his first ever draft with the philosophy: ‘It didn’t have to be perfect. It didn’t even have to make sense. It just needed to be at least 80,000 words long and have a beginning and an end.’ Wise words.
2. Don’t worry about being published; just finish your work to your own highest standards.
I honestly never thought, while I was writing my book, that it would ever see the light of day, but I still wanted to get it as good as I possibly could, for my own sake. Thinking like this will keep you focused on what's important. Worry about submission, agents etc, can come later.
3. Do find an honest source of feedback – and support.
Friends and family will often just think you're marvellous for writing anything at all, so I’d advise joining a writing group, either 'real' or online, or finding a critique partner who will be really straight with you (without making you cry). Literary consultancies can also be a good investment if you’re serious – try Cornerstornes.
4. When you receive feedback, do listen very carefully.
I know that it is easy, when you receive feedback that you disagree with, to want to explain why you wrote something a certain way or try to argue your reader into your point of view. Try not to do this. Instead, listen very carefully. Make sure you understand exactly what they didn't like and why. It’s up to you what to do next, but honest feedback is very precious.
5. Do think about the genre you’re writing in.
That’s not to say that you should be cynically writing to fill a niche (eg, one vampire teen romance with extra fries). But too often, authors finish a book without really thinking about whether their story is meant to be literary, or young adult, or romance, or crime ... Learning the rules of your genre (if you're writing genre fiction) will also help you construct your story. Whereas, if it's a mish-mash of genres, it might end up being quite disjointed.
6. Do remember: you could be published tomorrow.
It’s important not to despair about the publishing process when there are so many other ways to share your writing. Starting a blog is a fantastic way to practice and see how readers react. And remember, you don’t have to go from zero to writing a full novel. I started my blog and wrote several short stories before I embarked on a novel.
7. And finally ... do have fun with your writing.
Isn’t that why you’re doing it? Put in bits that make you laugh and cry, a horrible character you love to hate, a hero or heroine you want to cheer on ... If you like eating, put in some delicious meals; have fun dressing your characters in gorgeous clothes and describing beautiful scenery (not too much ...) Don’t panic and have fun!