Stand in “earth” with your outstretched fist facing your opponent.
With just a tiny bit of movement and adjustment on your part the opponent should be unable to get to any part of your body except for that fist. That fist should ideally be pointed right at their face.
Use this position when you’re 15 feet or so from your opponent.
Run towards your opponent while maintaining this position. This posture is very alive. As you close on them keep tracking them with the outstretched fist so that they have to deal with that before they can get to anything else.
As soon as you feel contact, either your fist hitting them or them hitting your arm, use your crossing fist movement to adjust the angle, parry and bring that other fist out while you run them over with whatever other Xing Yi stuff you feel is appropriate.
They should never see the second hand coming.