The clutch on a Civic (per your other posts) ought to be very light already.
Certainly nothing like the clutch on a 71 454 Vette I had years ago.  I know
of no fix to make an existing clutch softer.  If your clutch is heavy or
very stiff, you may have a problem with the pressure plate.

Clutch adjustment would solve no problems. I'd make sure all of the clutch
linkage is well lubricated.

What year and model have you got?

When clutches wear, especially the cable-operated ones), they get much
heavier in operation (you should feel MY clutch after 250K miles!). Also,
if the cable is worn into its sheath and is binding, this will increase
pedal resistance.

If the clutch is not worn and the cable (if any) is not binding, then
there's probably not much you can do. How does your car's clutch compare to
others?

I've accumulated 250,000km of hard driving on my clutch. I've also got a
stiff clutch pedal. Honda Dealership thinks that I need a clutch overhaul
and my personal mechanic thinks that the pressure plate is going bad.
However, since my foot is like a ton of bricks (as per my wife's description
when she tries to move it off her), the wimpy clutch pedal doesn't pose much
of a problem. My mechanic quoted me $600 to overhaul the clutch, which might
be a deal if the knee is in really bad shape.

Pars.
98 Civic Hatch