Allow yourself to make mistakes and learn from them. Be your own best friend, support yourself when things go wrong. Listen to what you say to yourself. Watch out for the negatives, for when you knock yourself back.
Give yourself a break. Accept when you have given something your best shot. If you didn't succeed this time, so what, have another go. Work out why you went wrong and what you need to do to succeed next time. Allow yourself time to build skills.