The best way to build muscle and reduce fat is to incorporate a combination of both strength training and cardiovascular exercise into your regular routine. Strength training should focus on compound exercises like squats, deadlifts, bench presses, and pull-ups, while cardiovascular exercise should include both low- and high-intensity activities such as running, swimming, and cycling. It is also important to create an effective nutrition plan that includes a balanced diet of proteins, carbohydrates, and healthy fats. Additionally, be sure to rest and recover adequately to give your muscles time to rebuild and grow. Finally, stay consistent with your workouts and diet and you will be sure to see results.