How do I use pistons for custom landing legs?

I normally put a spring attached to the end of the piston for support. Then I attach the piston to a floppy rotator and attach a floppy rotator to the end. Then I connect my leg. Then I connect the leg to the same thing the original rotator is attached to. I normally attach it all to a strut so that you can easily mirror it around the tank.

It depends on your landing legs you want. If you are making your own, you should just excitement, and check out other crafts with custom landing gear