Ensure you don't have any metabolic problems or other health issues that could cause your body to abnormally retain heat. If you do have such a problem, you should avoid using a sauna suit, because the increase in core body temperature could lead to fainting or other injuries.
Wear the sauna suit as recommended. You will want to wear it while working out, preferably while performing cardiovascular exercises, such as running or cycling. It is recommended to workout at a high intensity for 15 minutes twice a day, rather than once a day for 30 minutes. This will burn twice as many calories.
Eat a sensible diet, and eat five or six small meals a day rather than three larger meals. Eating smaller meals will help increase your metabolism, which will help you burn more calories at rest, and will also help you burn more calories while working out in the sauna suit.
Drink plenty of water. Since the sauna suit is burning off a lot of water weight, and you will be sweating a lot more than normal, you will need to take in a good amount of water and electrolyte-enhanced beverages, such as Smartwater, which has no calories.
Allow your body five to 10 minutes to fully cool off before removing the sauna suit and taking a shower. You want your body to stop sweating prior to showering, and ensure you get your core body temperature back down to normal before you remove the sauna suit.