I'm pregnant now, so can't work to the intesity I used to.
I was going to gym 3-4 times per week. I would do 30 mins of high intensity cardio, working at 95% of my Maximum Heartrate then do weights, working 2 muscle groups per session.
For instance day one would be Chest and Triceps, where I'd do 3 different exercises for each muscle group, 3 sets of 20 repetitions on each. Day 2 would be Back and Biceps and day three shoulders and legs. I'd superset, so I would move from one exercise to the next without rest.
It's important to work all muscle groups, not just the areas you want to slim down, so the bigger muscle groups will be the ones which help to burn fat, like the legs, glutes and back. (The more lean muscle you have on your body, the more body fat will be used)
What is also very important is diet. At the time, I was on a very low fat diet, although I continued to have essential fats. I only ate lean protein, with lots of green veg and my carbs would be small portions of brown rice or wholewheat pasta, never white.
It does take real dedication and discipline, but my body was at it's very best, as I wanted to enter figure competition. Unfortunately it went to pot a bit, when I met my now Fiance. After baby comes, I'll get back on track.