How do I make good Cylero parachutes?

@CanadaDucK ok.

For Cylero I do the same, Max inflation at High Altitude to catch all the Atmosphere they can. Note: this only works for Low Atmospheric Body's. I have Several MARS Builds with Parachute Set-ups. They can still take some Tweaking. For DROO my Parachutes open just before you Die! works well though.

@CloakPin I do it the same way as you do and it does not work. I have high physics and ultra update frequency.

I made mine as big as possible and made the deflation diameter be the same size as the inflation diameter.
Also let it open a max speed and not auto cut.
Default settings are for Droo I believe so just thin the atmosphere about 1/3 less and to release higher in the atmosphere for cylero chutes.