Red: My corrections

Blue: My comments

Have a haircut

I got my hair cut just now, I guess the hairdresser must be a new guy! I hope my hair looks like lively and lovely. Faced with my demand, he was cutting my hair carefully! He has cut for a whole hour! But nothing changed! I need another chance to cut again！

I think the sequence of the sentences you worked on needed to be better. Here's what I would say:

Getting a Haircut

I had a haircut just now and I had hoped that my hair looked better. The hairdresser must be a new guy because I asked him how I wanted my hair to be cut and he was very careful. He cut my hair for a whole hour but nothing had changed! I need to find another hairdresser!