Sad to say , but basically there is no short cut way of weight loss except for exercising & proper diets. You may see fast results for crash diet but it will not sustain and will lower your body metabolism in the long run.
For slimming center what you will be losing is just the water through wrapping ( you can do it in sauna/ suntan too), they will still recommend you what to eat & what not to eat.
Just imagine if u see a doctor for recommendation , the doctor will recommend you to exercise or go slimming centers?
Start your exercise with some strength training & cardio exercise , you can always start with a baby step at a time , with persistence you will be definitely able to achieve your goals!