HELP! child not listening

[bai]

My DS is 4 and a half. Recently he has stopped listening to us at home and in school. teachers are getting very frustrated, things are improving at home gradually. Most likely he will need an evaluation for ADHD. If he does have ADHD what can I do to help improve his listening? Does anyone have any guidance for this? He is also getting a little clingy everyday, tears with small things, maybe because both at school and home we are trying to discipline him. Maybe our ways are incorrect.