Oh no, that’s so frustrating! You’ll want to act quickly to avoid lasting damage, mold, or lingering odors.
First, open your car doors so your car gets some cross-ventilation and help air out the car.
After that, use a towel to soak up as much wetness as you can—you may go through quite a few towels! If you have a shop vac or similar tool, use the wet setting to suck up the moisture. A hairdryer also works in a pinch. Finally, aim several fans into your car to further dry out the vehicle. You’ll want to run the fans for several hours, at minimum.