I Am very Overweight.....How Can I Lose Easily And Look Thin?

I have a BMI of 34.7 which means obese..i want to lose fat easily...i want to become thin quickly..please suggest me some remedy except a diet plan..i don't want to diet..i used to go to gym..but i did'nt lose a kg and gained 10 kgs in a yr... PLZ HELP!!!!!! :((