To properly use a kettlebells you should hold the kettlebell in either one or both of your hands (depending on the move) doing a variety of exercises that include swings, presses and pulling exercises, some may require you to switch the kettlebell from hand to hand which requires you to use your core muscles in a new and different way than regular dumbbells. Kettlebell work outs are high calorie burners as well. I have so much fun when I am doing these exercises I hardly notice how hard I am working. The next day muscles I did not know I had are slightly sore, which makes me happy!
Some kettlebell exercises can be found at the following links:
Have a very fit day!