There’s useful advice out there on how to get more efficient in your running. That is, how to go farther or faster at your level of conditioning. Efficiency improvements come from what your legs are doing of course, but it’s also about your hips, torso, shoulders and arms.
Still, most guys aren’t so into running that they want to explicitly think about the angle of their femur in the push-off part of the stride. Or precisely how bent their elbows are. Or do special drills designed solely to change the way they run (“dorsiflex” your ankles, anyone?).
Based on my own experimentation with this stuff, though, I recommend you try these two form tweaks. They are 100% easy to understand, and don’t mess with your basic running style.