Lift the drain and unscrew the stopper. (Rotate counter clockwise)
This is the stopper removed for this style drain. Other types will look different.
This is what the drain piece will look like in the tub after the stopper is removed.
Here are a couple different types of plumbers drain wrenches. You can pick one up at the hardware store. They have different uses for each side of the tool.
Insert the drain wrench into the drain and rotate counter clockwise to loosen the drain. It will probably be pretty hard to turn and feel stuck, but keep trying it will loosen up.
You can do this by hand or using a screwdriver as a handle to get better torque on the tool. I'll show the screwdriver In another pic.....
After you remove the drain, you will see old plumbers putty or silicon. You need to clean this off before installing the new drain.
It will come off pretty easy. Just throw it away.
Here is the cleaned off tub drain flange with the drain removed.
You will need some plumbers putty to install the new drain. This is the kind I use. It's pretty cheap at the hardware store.
Get some plumbers putty out of the tub, you don't need much! I used a ball less than an inch in diameter.
Roll your putty into a piece about 5"-7" long and about as thick as a pencil.
Flip your new drain piece over and put the roll of putty around the lip of the drain flange.
Wrap it around and connect the ends. If your roll is too long just pinch off the excess. Press the ends together.
Flip it over and screw it into the drain on the tub, rotating the drain clockwise this time.
The tool I used to take the old drain out did not fit this new drain so I'm using the other tool I have to tighten the new drain.
This is how you use the screwdriver in the tool as a handle as for extra torque.
Tighten until you can't turn anymore. Some of the plumbers putty will squeeze out all around the edges.
Scrape off the excess putty.
This is how much excess I had.
Take the new stopper and screw it into the center hole in the drain. Rotate the stopper clockwise
Insert it into the little center hole.
This is what it should look like.
This type is is "twist and pull" so you turn the knob 1/2 turn and you can pull up or push down. If you pull up. Turn it 1/2 turn and it will stay up. Turn 1/2 turn again and you can push it closed.
Close the stopper and test the new drain for leaks. Fill the tub 1/2 full and let it sit to make sure it does not leak.
Put a mark on your tub to make sure the water level stays the same for more than an hour. You can use a dry erase marker, pencil or some people like to use tape.