Replace your toilet in about 25 minutes with these few simple steps.
Drain the Water
Shut off the water to the toilet. Then flush it until it's mostly empty, then manually remove the rest.
Disconnect the Toilet
Disconnect the water line, then unscrew the bolt(s) that connect the toilet base and floor.
Break the Seal
Score the calk line around the toilet, then rock it to uproot it. Remove the old gasket, and block the pipe with a rag. If the flange is cracked or warped in any way, you'll need to replace it.
Position Bowl & Gasket
Insert the new wax gasket into the new toilet's bottom; tapered side down. Then position the bowl in place.
Set & Fasten
Fasten the new hardware, but not too hard (otherwise you can crack the base). If the bowl isn't level, unloosen the toilet and add some plastic shims to balance it out. Do that by marking where the toilet is uneven, cut the shims to size and place them, then re-tighten and test. Do this until there is no rocking.
Attach Bowl to Tank
Insert the bolts through the tank, position it, and secure the bolts with washers.
Connect the Toilet
Connect the shut-off and fill valves. Tighten the compression nut, and open the shut-off. Test the toilet for leaks. If any water comes from the base, you need to get that fixed before finishing.
After being sure there are no leaks, apply a bead of calk around the base. Then smooth it out with your finger and wipe the excess.