Mix your butter, sugars, salt and vanilla until creamy and fluffy (about 3 minutes with a hand-mixer).
Add your flour and mix.
On a floured surface, knead the dough until smooth. Shape into a ball, cover in plastic wrap and refrigerate for at least 3 minutes.
Roll out the dough until it is about 1/4-1/2 inch thick. Then shape your cookies with a knife or cookie cutters. Lay on the cookie sheet and place back in refrigerator for 5 minutes.
In a preheated oven to 325 degrees, add your cookies for 15 minutes or until the edges just start to brown.