Removing the smell of gasoline from clothing involves blotting, soaking and washing the clothes. It's important to get this process started right after the spill occurs to stop as much of the fuel from soaking in to the fabric as possible. The most effective materials for removing the smell of gasoline, according to About, are baking soda, vinegar and a solution of warm-water and detergent.
First, use a clean white cloth to blot up as much of the excess liquid as possible, while being careful not to rub it in to the fabric further. Then sprinkle a generous amount of baking soda onto the stained area and allow it to sit for several minutes drawing the gasoline out of the clothing fibers. Remove the baking soda and mix a solution of detergent and warm water. Allow the stained article to soak for 30 minutes. If there's still a smell after soaking, repeat the baking soda process again, but this time rub it directly into the stain and allow it to air dry. Once dry, try a vinegar and water soak for another 30 minutes before putting the clothing through a standard wash cycle. As a last resort, if the smell still persists after these steps, add a little orange all-purpose cleaner to another wash cycle.