Let the engine cool completely
Park on a level surface
Open the hood
Locate the coolant reservoir and radiator cap
Check the coolant level against the marks on the reservoir
If needed, slowly remove the radiator cap only when the engine is cool
Use the correct coolant type for your car
Mix coolant with distilled water if required by the product label
Pour coolant into the radiator or reservoir slowly
Fill to the proper level mark
Replace the radiator cap securely
Close the coolant reservoir cap
Start the engine and let it run briefly
Check for leaks and recheck the coolant level after the engine cools again