Below is a list of steps you should follow when attempting to replace a toilet at home.
Turn off the water supply valve or the water valve to the house if there isn’t one at the toilet supply.
Flush the tank and hold down the flush lever to remove as much water as possible.
Remove any additional water in the tank and bowl with a wet vac or sponge.
Remove the water supply line at the toilet side connection by hand or with a wrench.
Loosen the two nuts(one on either side at the base of the fixture.Sometimes these are covered by egg-shaped plastic caps which can be removed by slightly prying with a flat-head screwdriver. If you cannot unscrew the nuts by hand you may need to remove them by some means of cutting such as a saws-all or hacksaw.
After the nuts are removed and the tank and bowl are empty you can then grasp the toilet underneath the point where the toilet seat bolts down on either side of the fixture.With two hands and a steady rocking motion side to side while pulling upward you should be able to remove the toilet from it’s flange at the floor.
Set the old fixture aside or discard.
Remove all old wax from the toilet flange at the floor and dispose in the trash.
You have now removed the old toilet and are ready to install a new one.