I was asked recently about ‘technique’ for cross-country. I was never taught this, and don’t formally coach it with youngsters, but it is true that you run slightly differently for cross-country.
The main problems are slipping and tripping. If you land on your heel with your foot well ahead of your body, you’ll end up on your backside! And if you run with your feel swinging forwards low before landing, you’ll end up tripping on the uneven ground. So cross-country runners tend to bring their knees through earlier and slightly higher, allowing them to then plant their feet downwards.
It turns out that this is a more effective technique on any surface, allowing you to run faster and with less risk of injury. So get out there on soft, rough ground, and work on that technique!