A good way to sweat is to perform a good workout. If your goal is to remove toxins from your body, you can go to the sauna or Turkish bath.
Other methods of eliminating toxins can be even wrap a strip of neoprene, or to even a plastic bag. While the latter can help in any way, the effect is only short term. Moreover, it would do more than is required and it would not be advisable.
You could not only remove the unwanted toxins, but also the essential water your body needs. However, if you mix these activities with a good workout then you really can achieve your weight loss goals.
With all that said, sweat is not the only thing you need to focus when trying to lose weight. You have to pair it with training, good diet and nutrition, and know supplementary in a proper way.