It took me about a year, from 165 kg to less than 130 kg, and I didn't rebound again. I only take exercise as a method, among which the easiest way to exercise is walking. Of course, the sooner the better, the longer the better. I never go on a diet during my weight loss. I can eat whatever I want. How can you walk without eating? So my personal experience is that exercise is the only effective, healthy and enjoyable way to lose weight, and it doesn't cost money.