My French part 2

I am sorry to report that my french let me down again the other day. I had gone to the hairdressers for a trim and had hoped that either the mother or daughter who work in the salon would remember how I have it.
Unfortunately the daughter was off and the mother was busy painting some white haired lady a rather fetching shade of maroon, so I got the lady who speaks no english.
I knew the word for thinning but that was about it. So I pointed at the ad next to the chair at the suave looking frenchman and said "comme ca" like that. "Tondeuse" came the reply, which I knew was clippers. "Oui" I said, "trois,s'il vous plait"
As the clippers made their first cut, I knew I was in the merde. Either she didnt understand trois and thought I said un or number 3 on french clippers is a hell of a lot shorter than in the UK.
But what can you say when the first thrust is complete. " oh, I've changed my mind, please stick it back" or " thanks that will do, I fancy a reverse mohican" (not that i could have said either or not in a language she understood?)
I said nothing, sat still while my hair made piles on the floor and then smiled paid my €10 and left to rush across the road to the supermarket to buy a bobble hat