@michelleyy,
This is my advice. You have to be disciplined, set yourself a target and stick to it. Write everyday. Don't delete anything, if you're not happy about it, forget it. It doesn't matter. Move on. Keep writing. Keep that up, and eventually you will have a novel. This may be a novel that you are really disappointed with, a novel you think is ****. A **** novel is worth one hell of a lot more than a load of really ******* good ideas.
Forget about it, put it to one side for at least six months, preferably a year. Don't read it, but let others read it, people you trust, listen to what they say. TAKE NOTES. Read books, watch films that are similar to your novel.
Six Months to one year later, revisit your novel. Think about the films you've watched, the books you've read, the advice your friends have given, and all the ideas that have popped into your head whilst you're asleep, or doing the washing up, or having a ****, or whatever. Rewrite your novel. Take your time. It may not be great, but at least you know it's no longer ****.
Now comes the tricky part.