What works for me (when I can be arsed, which is the real problem) is accurately counting the calories. Weight loss really is just a numbers game, eat fewer calories than you burn and you will lose weight.
I do it in a rather sad way, keeping a spreadsheet of everything I've eaten. It does require discipline in that you have to make a note of the calories on the packet, adjust it for the weight of the food you're actually having, looking up "average" values for fresh foods that don't have a calorie count on them.
Record everything you eat, even if you know that you are eating more than your goal. I usually exceed my target but at least by being honest with myself I know how much I am exceeding it by. When I weigh myself and I've not lost any weight, I can see exactly why (usually because I've stuffed my face that week).
The important thing is that even if you are eating too much, counting the calories accurately at least makes you think about what you are putting inside you. You then have the knowledge to make simple changes (one slice of toast instead of two is about 100 calories less, do this every day and it is 700 calories per week - about half of my daily target).
I'm now "overweight" rather than "obese" but I still have a long way to go before I'm a healthy weight. Personally I still don't feel confident about going to the gym but I make sure I get at least 30 minutes brisk walking done everyday, usually longer. Even short bursts of exercise get your metabolism going, meaning you burn more calories even after you have stopped.
It is important to realise that it is a long haul. You won't drop ten dress sizes in as many weeks, if you did that would be incredibly healthy. You have to look at it longer term, healthy weight loss is slow and there will be stumbling blocks upon the way. Very few people have the discipline to stick to a diet every single day for months or even years. I have many blips, but the important thing is to not give up when they occur. I've pigged out over Christmas and have put on a little weight, but so what? I "weigh in" weekly, but my weight will naturally fluctuate from one week to the next. If I look at the last three months, my weight loss looks a lot more pleasant and achievable.
Make little changes, be realistic about timescales, keep at it, and don't berate yourself for occasional lapses.