Slow down as quickly as possible. Make sure to check the rearview mirror before hitting the brakes.
Look in the space between the hood and the engine to see in front of you. Put your head out of the window and peer around the hood if this is not possible.
Head for the side of the road (use your turn signal); pull completely off the road and out of the way of traffic.
Turn on the emergency flashers if necessary. Do not attempt to drive again until the hood is down and latched or fastened. You can tie it down with a rope if necessary.