General Maintenance & Repairs - Fuel line quick disconnect - dumb question

So I've only been messing cars for the last 30years or so, but I'm stuck here.
HOW THE HELL do I use the little plastic split disc fuel/AC line disconnect tools.

I must be having a dyslexic day

(not for my Z28 but changing a fuel filter on my daughter's vintage Dodge Neon)

Thanks!

push the tool into the line while pushing the fuel line in then pull both apart. mine on my camaro is a PITA