Interestingly there is at least half a different type of bathtub drains. And the actual method of removing the drain stopper varies between models. But after removing the drain stopper, it is pretty much the same for all of them. The next section to remove after removing the drain stopper is the drain basket. You will need a tub drain wrench or a locking plier for this. These tools will fit right into the drain crossbars. After locking the wrench or the plier, you can turn the drain counterclockwise until it comes off.