https://www.youtube.com/watch?v=OWbImGvHnpk
Please click the above link for a detailed demo video of the Nagabandha Kolam.
Refer to the below images for step by step construction of the kolam.
Draw two concentric circles. Divide the inner circel intp 4 equal parts. Then divide each segment into two. Now we have 8 equal parts.
Again divide one eight of part into 5 equal parts. Now circle is divided into 32 equal parts. I have shown the division of the circle in red and blue dots for easy understanding.
Now the connecting the dots.
First choose a dot and count the 7th dot and connect by a curve or a semicircle touching the outer circle as shown
Now offset the curve towards the inner side by joining the first and 6th dot. connect the dots as said on all sides.
Total of 4 curves are formed.
Now repeat the same curve pattern with the remaining dots and form 8 curves.
The first set of curves flow with two lines while next four curves tend to look as if they have placed in the lower layer and the lines are cut for the celtic effect.
Connect the lines as shown and finish the kolam with head and tail.