Cardio cardio cardio. People usually like to look at it as calories in being less than calories burned, which is good, but the long runs that go for a couple miles every other day or so will do more toning and burn off the weight better.
Actually training your muscles in combination with cardio is more effective than just cardio. Exercises like burpees, jumping lunges/squats are great examples. They target your muscles, but keep your heart rate up as well :) Win-win.