I got a haircut today, and due to the season wanted to leave it a little longer in general, maybe more particularly on top. I got it communicated (the guy did his usual good job) by saying something like うえ、ちょっとだけきれいにしておねがいします。
In English, I'd've said something like: "just even/clean it (the top) up a little", or "just trim the top a little, but (try to) leave it long (as long as possible)", or "don't take much off the top".
Any suggestions for alternate ways of expressing something like this?