you should try rope skipping and strtching as a daily routine. Apart from this, I recommend full heart dancing on any of the song, without any hitch, as it works as aerobic & cardio both.
Run in place or sit on the floor and extend your arms out bent at the elbow and travel on your behind and go up and down on the floor...in just a few weeks you will notice the difference , and why not Yoga ? One of the best ex cerise in the world