So basically nothing works, because of any of the approaches you used to lose weight actually owrked you would have been able to stick to them and kept the weight off.
I lost weight (160 to 115) and kept it off for two years so far. I mostly eliminated sweets and other added sugars and added exercise (from sedentary to daily brisk walk on inclined treadmill 5 miles). It took about 7 months to lose it. I didn't count calories, measure anything, track anything, weigh myself frequently, fast, cut out meals or snacks, increase my water intake, etc.
I was probably eating 3000 calories for years on end to get that heavy (much of it from sweets and other junk) and it was easy to see what needed to go. I maintain my current weight with around 2000 calories and did not return to eating so much junk, but I am not super strict. I continue to put in my 30+ miles on the treadmill.