What diet can I do to get skinny?

I have done a calorie diet in the past and it worked very well in terms of me losing weight fast but I had to take laxatives weekly because it slowed my body down. I ended up gaining all the weight and some more back after the calorie diet. I have since tried plant-based diets, paleo, and more calorie diets and with some of them, I'll lose like a couple of pounds before not losing anymore and quitting it because it is not going well. Please give me some recommendations, I want to get skinny like how I used to be but I want it to be sustainable.