The way I did it with Kane is when he has a toy in his mouth, to get him to drop it at first, I wave a treat in front of him. He'll drop the toy to get the treat, I praise and give him the treat. After a bit, I added the Drop It command AS HE was dropping the toy, so that he understood DROPPING the toy is what I wanted.
Then, when he's Dropping the toy reliably, I really reinforced it by immediately giving him whatever he was forced to drop back. So, if we were playing tug and I told him to drop it and he dropped it, his reward was immediately getting the toy back to play some more tug.
Also, when you're teaching your dog commands, you want to make sure they understand what you want them to do before commanding them to do it, lol. That staring thing is what happens when they don't know what you want them to do.