In a bowl stir together by hand butter, sugar, brown sugar, salt, eggs, and vanilla. Do not use a mixer, these are better mixed by hand.  

Stir in oatmeal until well mixed. Stir in chocolate chips. 

Refrigerate dough for several hours. Do not skip this step or the dough will spread while baking. 

Preheat oven to 350 degrees. 

From dough into balls using about 2 tablespoons of dough. Place on baking sheet and bake for 11-13 minutes. 

Let cool on cookie sheet for about 5 minutes or until cookies are set and easy to remove. Finish cooling on wire rack.