Stay hydrate, and if you want to make this workout hard, perform the exercises slowly.
Warm-up your whole body,to prevent possible injuries.
Circuits Repetitions: 3
Circuits Execution: OneCircuitAtATime
Rest Between Circuits: 130 sec.
Rest Between Exercises: 35 sec.
Make your dynamic&static stretching,to prevent possible injuries.
Drink enough water, and get your afterworkout supplements (BCAA,Protein,Vitamines or whatever you use) .