These are the full instructions, courtesy of Mike Keen.
We wish you luck with them
how to make elves' boots
1. Lay out the napkin with a flat edge facing you
2. Bring the top edge towards you & place the edge halfway down the napkin
3. Take the bottom edge (closest to you) and place that halfway up, it should almost touch the top edge you've just brought down
4. Brush the top and bottom edges of the napkin (they should now be folds) flat
5. Take the top edge and bring it down to touch the bottom edge, brush flat again.
6. Touch your left index finger to the top fold an inch to the left of centre
7. Holding the right hand side of the napkin bring it down towards you so that the place where your finger is forms a corner
8. Put your right index finger on the newly formed corner and bring the left hand side of the napkin down so that it runs parallel to the right hand side - it should now look a bit like a paper aeroplane
9. Put your left index finger again on the point and fold the right hand side in again - as if you were making a narrower plane
10. Put your right index finger on the point and do the same with the left hand side. The napkin should now be a symmetrical point with the left hand side slightly shorter than the right
11. Now fold the right hand side over the centre until it marries with the left hand side, smooth it flat
12. Now the tricky bit! - keeping the napkin flat rotate it a quarter turn clockwise so that it's pointing left to right
14. Holding the top edge flip it over so that the fold is at the top and facing you should be the two edges - keep the point facing right.
15. You should have two flappy bits on the left, the top one slightly shorter than the bottom You should be able to see the bottom of the boot forming! - with your right thumb in between the two flaps bring the top one up so that it points towards the ceiling.
16. Keeping it pointing up, with your left hand take the bottom flap and fold it up & over away from yourself at the point where it hits the bottom of the boot. It should be forming a right angle
17. Put the top flap that's sticking up back down
18. Holding the folds flip the boot over from right to left so it's now pointing left
19. There should be a flap sticking out to the right, hold the right edge of this and bring it up & over the rest of the napkin to form the heel
20. This flap should now be tucked into the fold just past the heel, tuck it in securely, use a bit of force and jam it in and it'll round the heel nicely
21. Your napkin should now resemble a boot! - holding the heel with your right hand bring it upright, with your left hand squeeze the sole and bend the toes up to make it look a bit worn and also to enable it to sit up on the table.
22. The last bit to do is now fold over the top of the boot around itself, bend & tweak it a bit more until you're happy with it and put it on the table.
23. You can put nametags, scrolled menus, gifts etc inside the boot to personalise it