Answer:
A proper aerobic exercise plan, must contain low or medium intensity workouts that tend to focus on the improvement of the cardiorespiratory system, and to give energy to the body through aerobic respiration.
So, the best exercises are: walking, cycling, jogging, swimming and aerobic dance, there's no high impact, and they improve the cardiorespiratory system, and the heart.
This range of aerobic exercises must be focused on specific goals, like: keep using large muscle groups, constantly, maintaining an specific cardiovascular rhythm. Also, you need to set the principle of progression, that is, each day set a few minutes more, to ensure improvement everyday.
Lastly, hydration and breeding are crucial. Ensure to rest periods of 5 minutes between certain time intervals, not more than 5 minutes, because your heartbeat will drop.