Try this, it's delicious:
soy sauce - a cup or so per steak
sesame oil - not much maybe just 1 tsp per steak
chopped up green onions - enough for your liking
garlic - enough for your liking
Let it sit for atleast an hour in a zip-lock bag. Might have to flip over to maranade other side. Best to maranade as long as you can before putting it on the grill. Of course I don't do it until an hour or so until grill time.