In preparation for NaNoWriMo, one should first have a topic and secondly have an outline. At this stage research is invaluable and will save you time later.
How to outline your novel for NaNoWriMo. You must narrow your focus, outline your story, and plan accordingly to get to your 50K word count goal.
Planning for NaNoWriMo is difficult, however the first step one should take is to choose what they are going to write about all month.