1. Chart your progress. I weighed myself immediately after every single time I woke up in my own bed. This reduced the variance caused by non-standard time weigh-ins tremendously, and eventually I got to the point where I was able to predict how much I'd weigh to within half a pound or so. Some people say not to do this, and that might be true if your plan is to lose weight over the course of, say, a year. But for the 90 day 10% plan, just weight yourself every day and make a graph.
2. Work out daily, but do not kill yourself. I found that on days when I really pushed myself I just ended up starving and needing to eat more. Remember, your goal is to lose weight, not get into great cardiovascular shape. I literally rode an exercise bike for probably 30 minutes, 5 days a week, and that was about it. People are amazed by this.
3. Drastically reduce the size of your "meals". In order to do this I found it extremely helpful to basically eliminate foods from our pantry that were not "OK" for me to eat (I was able to do this thanks to Danielle's free food at Google), and stock the shelves with rice cakes, bread, and Coke Zero. For a full two weeks I basically subsisted off of rice cakes (I emptied Ralph's shelves at least 3 times over the course of this thing) and liquids, and the weight just melted off me.
4. I'm sure you've heard that if you starve yourself your body will realize what is happening, slow down it's burn rate, and that consequently you will not lose weight. I did not find this to be true during the 10% 90 day plan. What I did find is that the first week was truly truly awful because I was literally hungry 12 hours a day. I'd eat a "meal", be hungry again in an hour, then not eat for 3, and repeat. There were nights that I could not fall asleep because I was too hungry. Obviously this is/was not healthy, but the point is that once I got through that adjustment period I was able to eat the same portions I'd reduced myself to without getting ravenously hungry and correspondingly cranky. So if you're going to do this, pick an "easy life week" to get the ball rolling. Once you get through that week, the next 3 will be pretty easy and you should lose a ton of weight.
5. Trips are incredibly bad. I shot out of the gate like gangbusters, but spent most of the last 7 weeks out of town (I went to Vegas 3 times, San Francisco for 5 days, and Yellowstone for 5 more). The reason for this is that it is extremely difficult to control exactly what you eat on trips. You're very likely to drink (beer is extremely bad for this), go out to eat, and in general eat a lot of junk. My only advice is to bring your diet food (rice cakes and diet soda) with you and to use them to skip meals on the trip.
6. Do not give in to societal pressure or standard convention. You do not actually need to eat dinner. In the past I had problems whereby Danielle basically made dinner while I was still playing and then I got home and we ate together, even though I wasn't really hungry. Your significant other should and certainly will support your endeavor, and if eating dinner doesn't fit into your daily plan then (s)he will understand and happily eat pasta alone. If (s)he wants to go out to eat sometimes, that can be fine to. Danielle and I literally went out to BJs a few times where I simply did not eat. She'd order a meal, and I'd just have a beer (obviously not a great plan, but you have to have some fun once in a while). If you're not hungry, you don't have to eat. And if you are hungry, it is OK to eat 3 rice cakes and a lite yogurt for dinner.
7. Diet drinks. Do not drink any calories. Just don't, it's silly and you don't need to do it. The possibly exception is things like Naked Juice or Odwalla, that actually pass as a meal and do fill you up and provide some sort of nutrition. We've all heard that diet soda is bad for you. Maybe this is true, but it's certainly more than offset by the health benefits of losing weight.
8. I didn't count calories. Not once. Sure I looked at the nutrition facts on things and if they were extremely high calorie either passed or only ate half or whatever, but I had no actual chart of what I was putting into my body. Basically all I did was make a game of my life, eating as little as I possibly could and still functioning in a reasonable fashion. For some people I have heard that the mere act of writing down what you eat helps you eat less; if that's the case, by all means give it a try. But I did not take such a measure and things seem to have worked out fine for me.
9. Enter a prop bet or otherwise have a partner to help you out. This kept me extremely motivated through the first week (which as I stated was extremely awful), after which my actual success was enough to keep me motivated. In general, make yourself in somehow accountable for reaching the goals that you have set. I used money, but you could do just about anything you want. If I lose this weight I get to go on this trip or take these days off or buy myself this new gadget or whatever. I don't know what the financial value is of losing 10% of your body weight if you're slightly overweight, but it has to be pretty substantial.
And that is that. This has been one of the best things I have accomplished in quite some time. I feel great. I feel light, fast, healthy, and confident. If I can do it, you probably can too, because trust me I am in no way special when it comes to ability to not consume things. I'll leave you with a picture of my progress so far.