As previously mentioned, its about about 80% diet, 20% training. Cardio is great, but can only do so much. Lifting weights can help as it increases your metabolism so you are burning calories even when you aren't training.
But getting back to diet, you must:
1. Never skip breakfast
2. Eat at least 4 times a day
3. Eat clean foods
4. Eliminate carbs from your later meals in the day (say meal 3 and 4)
Regardless of how busy you are, if you dont get your diet sorted out you wont lose the weight you want.