Turn off the water supply
Flush the toilet to empty the tank and bowl
Disconnect the water supply line
Remove the old toilet if needed
Scrape off the old wax ring
Inspect the flange and repair if necessary
Install a new wax ring or seal on the flange
Position the toilet over the flange bolts
Lower the toilet straight down onto the wax ring
Press down evenly to seat the toilet
Install washers and nuts on the closet bolts
Tighten the nuts evenly, alternating sides
Do not overtighten
Reconnect the water supply line
Turn the water supply back on
Fill the tank and check for leaks
Flush several times to confirm proper operation
Caulk around the base if desired, leaving a gap at the back