which weight loss methods are you trying? you can speed up your metabolism rate by doing two things. And when i say 2 things, i mean you have to do BOTH.
1. Exercise. Not just cardio, but build muscle as well. Not bulky muscle, even lean muscle is fine. Muscle helps you burn calories even when doing nothing! Imagine being able to lose calories while sleeping.
2. Eat! I'm serious. You do have to count calories to lose weight, BUT you should never allow yourself to starve. When you're hungry for long periods of time, your body responds by becoming more 'efficient' in using calories. In other words, using less calories to fuel your body. Which also means lowering your metabolic rate. What's worse, if you don't eat enough calories, after using up your fatty acid stores, your body will start burning the proteins in your muscle tissue! Refer to point 1, loss of muscle = lower metabolism.
You might be thinking that you have alot of fat stored, you don't have to worry about losing muscle. Read again, it's the fatty acid that burns first, not your fat that has been solidified over the years. Those take alot of hard work to lose. That's why when people crash diet, they do lose weight, but it's alot of muscle weight as well, and they wreck their metabolism, which is also why they put back the weight so quickly, probably more than they lost in the first place, and they're going to find it even harder to lose weight again in the future.
So yes, increasing your metabolic rate is going to help signifcantly, but make sure you do it right. I keep a food diary too, with LiveStrong.com. The iphone app helps me record my food intake and exercises on the go.