1. Be calm
2. Take your foot off the gas pedal and turn off cruise control if on
3. Pay attention to how your brake pedal feels. If it’s soft and goes to the floor, you may have low fluid, or a brake fluid leakage, a faulty master cylinder or problems with your drums or calipers. You may be able to rebuild some braking pressure by pumping the brakes.But if your brake pedal is hard and does not move, check some thing like a bottle may have stuck under your brake pedal.
4. Pump your brakes. Pumping your brakes several times may rebuild enough pressure in the braking system for you to stop. This may take a while, so keep trying.
5. Shift into low gear. Shifting into lower gears helps slow you by using your engine to slow the car. If you have an automatic transmission, downshift a gear at a time into low range such as to "L".Be careful not to downshift too quickly; rapid downshifts into first or second gear can cause you to lose control.
6. Use Hand Brake / Parking Brake. The Hand brake / parking brake, can usually stop a vehicle, although it will take longer than usual to come to a stop because it only stops the rear wheels. Apply the brake slowly and steadily. It may lock your tire if applied too hard or too fast, especially at high speed. If you pull up the brake quickly, you may lose control of your vehicle. To prevent this, keep the release button engaged as you apply the hand brake.
7. Warn other drivers and pedestrians. Turn your hazard lights on, and honk your horn to make others aware that there is a problem.
8. If you have room on either side of you, steer sharply from side-to-side. Turning creates friction, which slows your car naturally. If you do not have brakes, try turning sharply from left to right over and over to slow your car down. But don't do this at high speeds. Turning at high speeds may flip your car and turning too sharply at any speed can spin your car around.
9. Use guardrails to slow your vehicle. Cement dividers are built pear-shaped so that contact is made with the wheels, not with the precious metal and paint of your automobile. Applying friction to the rubber on your wheels will slow the car considerably without harming other portions of your vehicle.
Video Source https://www.youtube.com/watch?v=83w4n5uC-uo