Prevent cookie dough from drying out by covering it with plastic wrap while it is chilling in the refrigerator. Freeze the cookie dough in an airtight plastic storage container. If air exposure has made your dough dry and hard to handle, you can restore it to an ideal texture with the help of a few ingredients. Dry dough will result in crumbly cookies so it's important to soften it before you begin the baking process.
Allow chilled or frozen cookie dough to warm to room temperature.
Place the cookie dough on a lightly floured surface, such as a counter top or baking sheet.
Knead 2 tbsp. of milk, cream or softened butter into the dough using your fingers. Work the moistening agent into the dry dough until the dough reaches the desired consistency.
Add cool water, drop by drop, to the dough while working it in with your hands as another option; keep adding water until the dough becomes moist.