Finding the right audition coach: You need to work with someone long enough so they can really learn who you are & help you sell your strong points. Start by finding someone you like. Do a little 'taste-testing'. There are many skilled coaches in the area - try a less formal clinic if possible before starting with regular private sessions. Then, just as with singing, dancing, or any other maintained skill, meet with your coach REGULARLY. Acting is YOUR passion, do some good with regular rehearsal & refinement.