How do I construct this into a truth table?

How do I construct this into a truth table? This is Philosophy. ~(N ∙ L) ∴ ~N → ~L

N L | ~(N ∙ L) ∴ ~N → ~L

---- | ---------------------

T T | F T T T  FT  F

T F | F T F F  FT  T

F T | T F F T  TF  F

F F | T F F F  TF  T

That's what I have so far