Find a piece of breathable fabric that you like. (I used a mesh fabric with patterns on it.)
Measure and cut the fabric to the shape of the door or window you are covering.
Staple the top of the fabric onto the outside of the door/window frame.
Once it’s stapled, cut a piece of nice looking wood to the size of the door/window frame and nail it onto the stapled area at the top of your fabric.
Et voilá!……The rest of the fabric is free to walk through or blow in the breeze!