Does anyone speak hairdresser? I need help communicating.

M49, I tend to go a bit long between haircuts which is on me, but I seem to have a really hard time explaining that I want short hair, like 20mm / 3/4"

I usually ask for a #2 clipper on the back and sides, (which works fine), then take as much as they off the top so I can still brush it straight up, preferably too short to grab onto.

Basically a cigar butt with eyes, shut up it works for me.

Even indicating with thumb and finger, this somehow gets interpreted as just barely trimming the tips off and painstakingly shaping the surface, barely affecting the overall quantity of hair.

How's that for length?

What no, get in there with fire and the sword, wreak devastation, I want all of this gone.

:carefully trims another quarter inch off:

It's not just one guy, not just one place, so I am obviously using wrong and misleading words.

How do I ask for the thing I want?