How do you change a thermostat on a 1996 Lexus ES300?

To change the thermostat on a 1996 Lexus ES300, first, ensure the engine is cool and disconnect the negative battery cable. Drain the coolant and remove the upper radiator hose connected to the thermostat housing. Unbolt the thermostat housing, replace the old thermostat with a new one (ensuring the gasket is in place), and reassemble the housing and hose. Finally, refill the coolant, reconnect the battery, and check for leaks.