Hiye! Try this: face a wall bit less than your arms length distance. Than do some push ups like. The trick is keeping your palms closer. (normal push ups your palm are at shoulder width distance, here you need to keep them much closer) Also keep your elbows close to your body. For more technical advices google for 3 moves for toned triceps. Good luck!
http://www.fitsugar.com/10-Minute-Arm-Workout-Video-22959099
You need to lose fat to tone a muscle!
It is not possible to lose fat off of only your arms. This means that if you want to tone your arms you need to start a weight loss program that will help you lose weight off of your whole body.
When your body has a low body fat percentage that your muscles will start to show defined and firm.
Women worry about getting bulky but this is not a problem as women do not have the necessary testosterone to get big.