New year is coming, and I'd like to lose weight, but I don't want to do exercise, because I have no time and no energy to do that after work.
SociallyChallenged pretty much summed it all up.
If your goal is to lose weight and you don't want to exercise, all you have to do is change your diet. That's it. There are basically 2 paths to losing weight:
1. Eat right
2. Exercise a lot
You can eat right and not exercise and lose weight. You can also exercise a ton (like 2 hours a day) and eat whatever you want and lose weight. Or you could do a balanced approach of eating right most of the time and throwing in some exercise. If you want to lose weight and you don't want to exercise, then you'll need to be strict about what you eat. I know plenty of people who never exercise, but because they eat healthy, they are skinny.
The best way I've found to do that is to create a meal plan that contains 5 to 7 small, healthy meals, where you eat every 2 to 3 hours (like half a sandwich or a protein shake). Eating small, healthy meals that often turns your metabolism into a fat-burning machine, so you lose weight without exercising. Although I'd still recommend at least 10 minutes of walking or something every day to at least stay in
some kind of shape. Also, it's easier to fight cravings because you're always full, instead of getting hungry between 3 big meals during the day like normal.
The key to this is the words "meal plan", not "diet". Diet is a short-term thing, which means that when you go off it, your weight will come back. Diets don't work because they are short-term: they are designed to make you fat again when you finish. A meal plan, on the other hand, is something that you can easily follow for the rest of your life. The easiest way to create a meal plan is to design a 4-day rotating menu, where you don't eat the same foods for 4 days in a row. I'd recommend 7 or even 14 (I do 14) days for great variety. Then creating a shopping list and make sure you keep all of the foods in stock. There's a great thread that lists pretty much all of the good stuff to eat here:
http://forums.anandtech.com/showthread.php?t=162171
I currently have a 14-day rotating menu with 7 meals a day, with a shopping list and what I call "daily meal plans", which tells me what to cook every morning for that particular day. I don't have to think about food, like, ever. I've also figured out how to make really delicious meals from healthy foods. Healthy foods are only gross if you don't put any effort into it (i.e. googling), so you can eat awesome-tasting meals all day if you figure out what you want to eat and then go shopping for it and make it every day. I do all my cooking in the morning so that I don't have to worry about it the rest of the day (takes 20 or 30 minutes, tops).
The healthiest amount to lose is 2 pounds per week, at most. I think most people recommend about 1.5 pounds. If you lose weight too fast, you'll get that excess skin that looks like flubber. The best way to motivate yourself is to create a plan and then document it every day. So first, figure out what your ideal healthy weight should be. Here's a pretty good calculator:
http://www.halls.md/ideal-weight/body.htm
Then subtract that from your current weight to figure out how much weight you need to lose. So if you weigh 220 pounds right now and you want to be 180 pounds, then 220 - 180 = 40 pounds. Next, assuming you lose about 2 pounds a week, then 40 pounds divided by 2 pounds a week is 40/2 = 20 weeks, or about 5 months. So now you can easily see that by simply changing your diet, in 5 months you will be at your target weight without exercising (but I do recommend exercising! lol).
It also helps to keep track of your results. I don't weigh myself daily, but I do weigh myself once a week. Even weekly tracking isn't really that accurate, since your first week or two or three is just waterweight that you're losing, so it comes off fast at first, and then really slooooow as you get towards your ideal bodyweight. Even so, just get a calendar, tape it to your fridge, and keep track. Find something to write down every day, like what you ate that day. Out of sight, out of mind - make sure it's visible every day and that you write something down to track every day. I don't recommend writing your weight down every day because it's like micromanaging yourself, when the results don't come that quickly (it took you years to put that weight on, remember?

).
HTH.