Having attempted and failed at NaNoWriMo several times, here is my advice to help you avoid my mistakes.
First let me say this: If you do nothing more than participate daily by devoting time to your writing, no matter how many words you end up with at the end of the day, that is an accomplishment, in and of itself. It helps you develop the beneficial habit of prioritizing your writing and incorporating it into your daily routine. If this is all you gain from NaNoWriMo, it’s still a definite gain.
If you find it daunting to write 1,667 words a day in one go, break your writing time up to 2 (834 words), 3 (556 words), or 4 (417 words) separate writing sprints over the course of your day. If your word count falls short one day, make up the difference by folding it into your next days writing. Whatever you do, don’t get distracted or discouraged by your word count. Just focus on your writing. Some days the words will come easy and flow out of you, and some days it will feel like you’re excavating them from stone. Just put the words on the page as they come.
For your best chance to win at NaNoWriMo (which is to say, achieve the goal of writing 50,000 words in 30 days), it is advisable to go into it knowing what story you want to write, who your characters are, what their desires/fears/goals are, what scenes are necessary to the core of your story, and what outcome you predict for your ending. You don’t have to know every single detail but the more you do know, the less chance you’ll have of getting stuck or veering off-track. Spend September and October planning and researching and pre-writing, in order to know and understand the story you’re going to tell and the characters that will populate it. That way, when November arrives, you’ll be ready to dive right in and write it.
Good luck to all those who decide to participate! I’m probably going to give it another shot, myself.