Individual Exercises

Skip Rope

With a proper jump rope, start skipping. You can begin with alternating feet - one foot leads the other over the rope (switch the lead foot occasionally to develop symmetry). Add segments where you jump with both feet at the same time. Work up to longer periods of two-footed jumping. If you need a break, stop for a few seconds and then continue.

Alternatives

Jog in place: keep your head up and your hands loose. Land lightly.
Jumping jacks: the grade-school classic! Land lightly, and make sure your knees point and flex in the direction of your feet. Avoid having the knees flex inward or outward when you land.
Step ups: more advanced