Make sure your feet land under your centre of gravity. If your foot lands in front of you, you’ll be heel striking – which means you are putting the brakes on with every step and you’re probably on a pathway to injury
Land flat-footed allowing your arch to absorb the impact
Try to land as lightly (and quietly) as possible
Keep your feet and ankles relaxed – I find relaxing my wrists helps me relax my ankles
Keep both feet facing directly forward, don’t angle your feet out (pigeon toed) as this will stress your knees
Don’t push off, focus on lifting your foot. Propulsion should be coming from gravity (your forward lean)
Running barefoot or wearing minimal shoes can help make you aware of how your foot is landing
Have someone video you running so that you can check your technique