Don’t try to open the door. Water pressure makes this extremely difficult to do. And even if you could open the door, this would allow more water to come in and make y our car sink faster. Instead, quickly roll down your side window, unbuckle yourself, and climb out. If you were too slow to react, the water pressure could pin your doors and windows shut. That means you’ll have to break a window. Don’t try the car’s front windshield as it’s built to resist impacts. Instead, go for the side windows. Use your foot and kick at the top of the window or remove the headrest from your seat and jam it where the window meets the door.
You can also use a glass breaking tool like ResQMe to quickly break the window. It can easily be stored in the glove compartment or on your keychain. If the car is upside down and your seatbelt is locking you in, the tool can even cut you free.