Supersetting is a weight training principle which involves working opposing muscle groups consecutively, an example superset would be bench press followed by cable row performed one after the other with no rest. Working out like this helps you burn more calories, raises your metabolic rate and gives you a tremendous pump.
Here is a upper body superset workout for you to try. Do the Superset workouts in pairs one after the other with no rest between the 2, rest for 30-60 seconds between supersets and repeat each superset 3 times. Do the workout twice a week with at least 1 days rest in between.
Perform 8-12 Repitions in each superset.
Superset 1 Bench Press/Bent Over Row
Bench Press: Lie on your back on the bench, push the bar up with a wide overhand grip and slowly lower it to your chest, push it back up to the starting position.

Bench Press Diagram
Barbell Bent Over Row: Hold the Barbell with a overhand grip, your hand just beyond shoulder width apart. Keep your knees slightly bent, feet shoulder width apart. Bend at your hips till the bar is about shin height. Pull the bar up to your chest pause, lower it in a controlled manner.

Barbell row
Superset 2 Lat Pull Down/Shoulder Press
Lat Pull Down: Grab the bar with an overhand grip, hands should be just beyond shoulder width apart. Keeping your head and back straight pull the bar to the top of your chest. Pause, slowly let the bar rise back up above your head. Don’t lock your elbows.

Lat Pull Down Diagram
Shoulder Press: Grab sit on a bench and grab Barbell, Hands just over should width apart. Slowly lower the barbell to the back of your head, push it back up.

Rear Barbell Press Diagram
Superset 3 Dips/Barbell Upright Row
Dips: Get on the Parallel Bars push up so your arms are fully extended, bending your elbows slowly lower your body until your upper arms are parellel to the floor. Pause then push your self back to the start.

Tricep Dips Diagram
Barbell Upright Rows: Grab a barbell with an overhand grip, feet shoulder width apart knees slightly bent. Let the bar hang just below your waist, hands touching your thighs. Bending at your elbows pull the bar straight up until your arms are parellel to the floor, pause then slowly lower to the start.

Upright row diagram
The above will get your fat off in no time, its important to work your legs aswell. More on that another time.
Images cam from the Training Station.com