Take your square napkin, lay it totally flat before you, then fold it in half horizontally.
Fold again, this time vertically so that you have before you a square a quarter the size of your origonal square.
Only one of the 4 corners will have 4 open or loose edges. Rotate the square before you so that it looks like a diamond with the four open edges pointing to the bottom.
We will call the points on your diamond shape East, West, North and the open egded bit, South.
Make a horizontal fold between the East/West points, bringing the open ended South point up to meet, and on top of, the North point.You will now have a little triangle.
Take the East point of the triangle and fold it in towards the middle. What was the sloping right hand edge of the triangle is now a vertical edge running down the center of the triangle and there is a little flap sticking out at the bottom.
Take the West point and fold it into the center the same as you did with the previous East edge, the two vertical lines should meet in the middle, and you will have a diamond shape that has two long sides at the top and two short sides (the two little flaps) at the bottom.
Pick up your diamond shape and fold the two little flap bits at the bottom completely under, so that they only show on the back of the triangle. The front will now look like a steep triangle with a vertical slit down the middle.
We will call the points of this triangle East, West and North. With the flaps still folded to the back of the tiangle, fold the East and West points backwards until they meet, and gently crease the two folds that form and meet at the North point.
The slit in the front will have opened and the 4 open points of the napkin will be hidden in layers inside. Pull very gently on them one by one and they will stand up like the sails of a boat. Some people I know call this napkin a boat, some a flower and some the Sydney Opera House.I don't know its' offical name but set onto a plate or into an empty wine glass, this a very elegant addition to a classy table setting.
