Good suggestions above. But especially, do sets of 10 burpies every minute. Focus on technique and posture, and try to get the set done in 30-35 seconds so that you have almost a half minute to rest between sets. At my gym, you have to be able to hit 10 sets in 10 minutes to make blue belt. Black bets have to do 300 in 30.
It's great cardio, great burst training, and a great mix of targeted muscles. And just in case you are not sure, a burpie is:
Start w legs at shoulder width, squat down, hands right outside your feet on the mat, kick both feet back at the same time into pushup position, pushup, jump feet back to where they were, jump back up with proper squatting technique, but jump in the air, and make sure to raise both arms over your head as you jump (to open your core).
Also leg lifts, windshield wipers (like leg lifts your feet go side to side like they are drawing a rainbow over your waist), and the above stuff, like hindu pushups. Also, if you don't mind looking ridiculous, practice balancing upside down. It helps for passing a lot.