Constant nervousness is not good for heart health, which would easily lead to high blood pressure. High blood pressure can cause dizziness, and in some serious cases would make people fall down and have unclear awareness. Given that these symptoms, how to lessen or avoid nervousness is worthy of trying.
Deep breath. Take a deep breath, consciously breath in and breath out. After doing the exercise, your heartbeat would increasingly drop down and you could feel less nervous.
Meditation. Slow down your mind and focus on your breathe. Feel your breathe going through the area between your nose and your mouth and keep your awareness on the position. When you find you’re distracted by some things in your mind, you call on your awareness to put your mind on that area again. Usually you can not last a little while at first; your mind would be occupied by other ideas and you hardly keep focus on your breath. But, as long as you often practice it, you would persevere in it longer.
As with the first way, you can do it anytime and anywhere. About meditation, you’d better be in a quiet place to practice. As a result, I recommend you try the first.