I use thicker meat, nearly an inch thick and partially freeze it. I slice in into slices no more than 1/4 inch thick (being partially frozen helps stiffen the meat for slicing).
I marinate overnight in a brew of worchester sauce, soy sauce, black pepper, and sometimes something else, a big mixing bowl works well.
Something else can be Teriyaki sauce (in which case I don't use the worchester sauce and limit the soy), Hot sauce (my favorite being Tabasco), garlic (yummy, and the wife's favorite), etc.
If you take whole cloves of garlic, clean and slice them, put them in the brew for a night, and then strain them out, before you add the meat you can smash and dehydrate them seperately for a great broth starter.... It's really good on chicken oriental style, or to flavor your water for rice...