As a gate agent, I see customers that have a fear of flying almost daily. You are not alone!!
Here are some tips that may help.
1.) Advise the agent that you have a fear of flying. If it helps you to board early or last, let us know, it's okay.
2.) Do not drink alcohol, that just amplifies your fears. I've had to deny boarding or remove customers due to being intoxicated, that does not help! You must be able to comply with the Flight Attendants instructions for your safety and the safety of others.
3.) Sit on an aisle or window which ever you would be more at ease with. You should pre-reserve your seat before you get to the airport. Airlines charge for these seats, so book early or you may end up in a middle seat.
4.) Bring audio and/or video with good earbuds to distract you after you are buckled in.
5.) Eye mask and a good pillow to sleep.
6.) Let the Flight Attendant know about your fear, they are there for your safety and have had lots of training.
7.) If it helps you, ask to talk with the pilots. ASK... if they have time, I am sure they will speak with you. They too are there to help ease your fear. I know that my husband (very senior Captain) has gone back to talk to passengers over his 28 years of flying. It is okay.