Make sure your maintenance is up to date - air filter, etc. Run the thinnest recommended oil and use synthetic - differentials also. Manual locking hubs will reduce the amount of drivetrain that you're turning while driving. Take any and all unnecessary weight out of the vehicle.

After all of that, adjusting your driving style is still the best way to get better mileage. If you're serious about wanting better mileage then lose the heavy foot and coast as much as possible.

95 Montero SR
3.8 MIVEC, Advance headers, 2 1/2" exhaust, Magnaflow muffler, OME shocks & rear springs, 2" body lift, 3" tank lift, 4.90s, TRE front locker, factory rear locker, Roger Brown Rock Sliderz, 315/75r16 (35") tires, Sport big brakes