What is a one-sentence summary of the following article?
First thing’s first—before you get too worried about how to clean a gasoline spill, you’ll want keep it from getting any worse. If you’ve accidentally knocked over a fuel tank or container, return it to an upright position immediately and secure the lid or cap over the opening. If the spill originated from a pump, make sure that it’s shut off and that the nozzle has been replaced.  Even a small gasoline spill can quickly become dangerous. Try to react as quickly as you can. Always pay attention when you smell gasoline fumes. Strange odors could indicate the presence of a spill, even if you’re not aware of it. Be sure to let an attendant know about sizable spills and leaks that occur at filling stations. Assuming the spill is the result of an ongoing leak, it may not be possible to stop it immediately. In this case, look for any sort of large container you can place beneath the leak. This will keep it from coming into contact with other surfaces that are much more difficult to clean.  Make sure the container you use won’t leak or overflow. If you’re at home, grab a bucket, paint roller tray or washtub. To prevent the spill from spreading to a larger area, throw down some object or group of objects that can stop or slow its movement. An obvious choice is a beach towel, but a piece of lumber or a few heavy boxes may also work (keep in mind that whatever you use will likely have to be thrown away). Position the barriers closely around the perimeter of the spill.  Be especially vigilant in preventing the spill from reaching electrical equipment or objects that produce or give off heat, such as stoves, space heaters and electrical outlets.  Use a plastic tarp to cover and protect objects that are vulnerable to damage. Gasoline emits powerful fumes that can be very harmful to inhale. Open all nearby windows and doors to get air circulating through throughout the room. If the spill occurs somewhere inside with no windows, turn on the ceiling fan or air conditioning.  Exposure to fumes may cause dizziness, lightheadedness, shortness of breath or disorientation.  Gas fumes are also a severe fire hazard. Avoid doing anything that may lead to an accidental ignition.

Summary:
Stop the spill at the source. Catch gasoline that’s actively leaking. Put down a barrier of some kind. Ventilate the affected area.