Nervousness is as much a reason for failure as much as lack of preparation or anything else. This reason single handedly ruins your hardwork, patuence and devotion making yiur goal unachievable.
Heres some of the things thta i have learned after failing or not achieving my set target
Overconfidence - No matter how great a genius you are, Overconfidence will ruin you.
Expect the worst-Prepare for the worst case scenario and hope for the best, hope is a weapon.
Hold your nerves-Getting irritated, anxious would only harm you try to calm down,
Try to be hydrated-helps maintian your stress level.
When in extreme stress lie down, this relieves you of your stress, when you lie down your body sees this as a more comfortable way of being yourself and your body has a proper flow of blood and you feel better.
Calm down-Studies have consistently proven that being calm and cool helps your brain to function properly and take relevant and better decisions.
Believe in yourself - Believe that you can achieve it but dont let this turn into your Overconfidence.
Stay positive-By this I mean dont be mean to yourself and take criticism with a straight face and take it on the chin.
Have a cool down period- Set some days or hours as that, if, you are not able to achieve your goal would be enough to get over this feeling of sadness and utter disgust.
You will be successful if you donot let Nervousness get better of you however a little of it is necessary to be successful in life, God bless you.