Whether you drive a hybrid or a pickup truck, there are plenty of things that you can do to improve your fuel economy. First of all, be careful about how you drive. Accelerate gently and evenly, don't go too far over the speed limit, and don't stop too quickly if you can help it.
Next, keep up with your basic vehicle maintenance. Keep your tires properly inflated, and make sure that they have enough tread. Don't go too long without an oil change, and replace your engine's air filter regularly. Not only will this extend the lifespan of your vehicle, but it will improve your gas mileage as well.
Finally, be careful how you use your car. There will come times when you need to haul some heavy cargo, but those times should be relatively few and far between. Putting too much weight in your car will force it to work harder and use more fuel.