First, preheat your oven to 350 degrees fahrenheit.
Then, mix in the flour, baking soda, salt, oats and cinnamon in a medium sized mixing bowl until combined.
With another mixing bowl, beat together the butter, shortening, and sugar until the mixture is light and fluffy.
Then, add the eggs one at a time, mixing completely together, and add in the vanilla extract.
Next, mix the dry ingredients with the creamy butter mixture until you have a dough.
Then, you can fold in the chocolate chips/raisins etc into the dough.
Either use your hands to make rounded balls of dough, or a cookie scooper to add cookies to a lined cookie baking sheet.
Finally, place the cookie sheet in the oven for around 10 minutes, until the cookies are golden brown in color. Remove from the oven, and leave to rest for 2 minutes before transferring to a cooling rack.