Combine all ingredients aside from the blueberries in small jar or bowl that can be sealed. Stir well.
Refrigerate overnight. Before eating, add blueberries. You can put them in when you make these at night if you know you will be in a rush but I prefer putting them in right before I eat them. Serve heated or cold.
Notes
I like to eat my warm and usually will add a splash more of milk before I heat them up or I feel the oats dry up a bit.