Spot training is not possible. To burn arm fat you must eat less fat-enlarge arm muscles by lifting weight-four sets of eight repetitions. Then, as your arm muscles enlarge and your fat decreases-you still will not be burning arm fat-but you will receive the results you are looking for. The only place spot training has been shown to work (maybe slightly) is in the thighs during biking or spinning. But, you did not ask this question.
You should work your arms every-other-day. Pull ups are great-push ups are good-lifting hand weights is fair. Best way to burn any fat-raise the heart rate. Run, walk quickly, Olympic style weight lifting pumps up the heart to am amazing degree-buring fat like mad. The plyometrics of the squat lift burn fat almost over night. But, eat lots of protein of your muscle will fade too.