I was taught and have always practiced turning the steaks and pretty much anything else on the grill with two sides, including sliced veggies only ONCE. Don't salt raw steak meat on the grill but wait to do it on a cooked side otherwise you get that nasty coagulated blood festering to the top.
The amount of time per side depends on the thickness of the steak.
Also very important get the grill up to temp before putting anything on it and set it up for a direct grilling
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