“Make a right at the next light.”
You're riding in a car with your friend. Your friend is driving but she's never been to the store that you're going to. You tell her where to turn.
Make a right at the next light.
When you're giving someone driving instructions, you can tell them where to turn using the phrases "make a right" or "make a left". This is a little more casual than telling someone to "turn right" or "turn left".
When you're talking about driving on a street, the phrase "the light" usually refers to a traffic signal. For example:
I think we were supposed to turn at the last light.
You can let me out right after the light.