This might be a little more hard-core than some people are doing, but I found a couple things that people are doing to prepare for the original NaNoWriMo, not the Miz version.
This is a PDF that is a guide to creating a "Professional Plot Outline". Considering I am a self proclaimed failure at plots, I thought this would be an interesting read.
6 Steps to a Perfect Plot is a little more than what we need for the Miz challenge, but what better time to start developing a plot for your PC than in a month you're dedicating to writing?
I found
this interesting as well. It was easy for me to take this and use the same advice on a more short-term idea.
Personally, I think the best best best idea is to ignore your word count. Just like boiling water, it is going to go by even slower if you constantly keep checking the exact word count of your posts. Just write. And keep writing, because the first week or two of the challenge is going to be the easiest. You can look anywhere on the internet and they are going to tell you to go above and beyond your word count in the beginning. This is so that if you have a day where you absolutely just don't have any time, you won't screw yourself over. If you have an idea that will just double your word goal for that day, do it! Don't split it up into two days!
If you're feeling uninspired, or the words just aren't coming out, don't give up. If that day is a bust and you maybe manage a couple hundred words, set yourself up for success the next day. Instead, open a word document or whatever and just type. It doesn't have to meet your standards for a post, it doesn't have to make sense to anyone but you, just get the words out.
Also, I think another good tip is to do what you're usually do when you write. For me, I have to find a quiet place where I can tune everything out when I start writing. After I get into the zone, it doesn't matter, but if I am distracted in the beginning I'm not going to get anything done. Lots of people are saying to play music, get some food, do this do that, go outside, do a jig.... but I can't. I can't listen to music or eat anything while I'm writing. I just can't. It'll disrupt my flow. I have to find somewhere silent and comfortable so if I'm sitting for an hour or two, I won't feel the need to get up and rearrange into a more comfortable position.
So, long story short, I think one of the worst things you can do is to change what works for you just because you have a goal in mind. Take other peoples tips and change them to work for your situation.