Work in short bursts (15 or 20 minutes) with short breaks in between. Do not pause to look up a fact or check your phone. Do not stop until the time is up. Then reward yourself with a short break (or a biscuit!)
Follow authors, editors, agents and publicists you like. Talk about the books you love. Follow hashtags like #writingcommunity, #amwriting & #writingtips.
Bored of staring at a blank screen? Want a walk but feel guilty leaving the desk? There are some brilliant apps that allow you to dictate your work and upload to your manuscript. It also really helps you listen out for errors.
To stay motivated try entering short story or flash fiction competitions when not working on your novel. This is great for experimenting with different voices and styles, making contacts and can also give you some much needed encouragement if you get shortlisted or win!
If submitting to agents: be professional, follow their submissions guidelines and try to tailor your submission to them. Check the acknowledgement pages at the back of favourite books to discover agents you might suit.
You will be rejected. You will be edited. If you do not handle constructive criticism well traditional publishing might not be for you. Learn to see rejection and feedback on your work as vital parts of improving as a writer. And keep going!