How do you change thermostat on 97 Toyota tercel?

To change the thermostat on a 1997 Toyota Tercel, start by ensuring the engine is cool and disconnect the negative battery cable. Drain the coolant from the radiator, then remove the upper radiator hose connected to the thermostat housing. Unbolt the thermostat housing, take out the old thermostat, and replace it with a new one, ensuring the gasket is properly seated. Reassemble everything by reversing the steps, refill the coolant, and check for leaks.