Use your hand, open your palm touch the meaty part of your palm ( under ur thumb ) with either your pointer finger, middle finger, index, pinky(ur using 1 hand btw)
(general idea of how ur meat should feel)
Pointer finger = Rare
Mid = mediumish rare
and so on..
But lets be honest if u want a nice done steak the best is to try it out!! Try to keep all your steaks about 1-2inchs thick, know your grill!(hot spots vs cooler spots), ALSO your steak cut ( tenderloin sirloin, etc) will effect ur cooking time a bit.. so best is to stick to one kind of cut..
I also like to time my steaks( i always look away or do other things so i tend to forget about my food i put on the grill )
1-inch thick steaks, i set my timer for 3-4 minutes each side (rotating it a bit after 1minute to get a nice checker mark)
Also try to flip your meat only once!!! dont keep turning it!! and overall dont play with your food! ( dont press it, dont flip it around constantly, dont move it )
( forgot to add rest your steaks, just let it sit for a couple of minutes

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