Crank your grill up to a hot searing temp and quickly sear on both sides over heat until your target temp is reached, watching (do not walk away from the grill) with a fast-read, high-accuracy food thermometer.
For this portion of the cook, you’ll want to make sure you’re using a high accuracy food thermometer and let your steaks come up to an internal temp that is 10° –
Pull them off the grill and set them aside at this point, then increase the heat of your grill up to a hot, searing temp (preferably 600° or hotter if possible).
For this portion of the cook, it’s ideal to also use a high accuracy food thermometer, but it’s even better if it’s a fast-read thermometer since every second counts when you’re searing at high temps.