How can I remove the drain stoppers in my bath tubs?

All of the tubs in my home have those drain stoppers that you step on to close and drain the tub. My tubs are always slow draining because the least little bit of hair (and I have LONG hair) will stop them up. I want to remove the stoppers. Does anyone one know how?How can I remove the drain stoppers in my bath tubs?
Once you take the cap and gasket off the cartridge should have a large slot for a screwdriver in it. Unscrew it. Remove hair from body of stopper and re-install.How can I remove the drain stoppers in my bath tubs?
Try turning them counter clockwise when the stopper is up. It should unscrew.
Clamp on a vice-grip pliers and yank it out!