Here is one of my very favorite high intensity interval training (HIIT) workouts. The first move of each of the circuits is meant to get your heart rate WAY up - it's the high intensity move. The following two exercises will be your active "rest". Alternating between intense activity intervals and lower activity intervals has been shown to burn more calories than steady state cardio by increasing your metabolism longer after your workout.
All you need is a timer (your phone!) and some weights (dumbbells or use water bottles if you don't have weights).
Let me know if you want me to lead you through this or have any questions. I would love to help!