First of all, you should do a little research on internet and also watch some videos for knowing the positions and accurate way of doing oblique crunches in a perfect manner.
You should lie down with you back on the floor. Use an exercise mat which will help you to feel comfortable while lying on the floor. Make sure your back is straight on the mat.
Now raise your knees upwards while keeping your back, hips, shoulder and head on floor. Then raise your right foot and cross it over the left knee.
During this process, your hands should rest behind your neck which will help you to use your abdomen muscles to perform the task effectively.
Now you should lift your shoulders and upper back from the ground. Make sure your lower back does not move upwards as it should rest on the floor.
After that you need to twist towards left and touch the inside of your right knee with your left elbow. Your right elbow should reach towards the wall that is behind you. Make sure you keep both elbows quite straight.
Try to use your abs when you lift your upper body upwards and do not use the momentum of body to complete this exercise. It will help in putting stress on your abs which will help in burning the fats from your love handles.
After completing the one side, repeat the process with the other side by following the similar rules. Try to complete 10 to 15 raps in one set and complete three sets on a regular basis.
With the passage of time, either increase the raps of oblique crunches or increase the sets which will help you to notice the positive change appearing in your body shape in just 2 to 3 weeks.