What are some good ways to loose weight??

ive already tried atkins and that doesnt really work for me. im really athletic and i run miles but i cant loose any wieght ...i dont get it because i eat really healthy too, sometimes, . but ive been on weight watchers and i did really goood and lost forty pounds but now i cant find the motivation or what to do to start loosing wieght again..please anything will help!! thanks