spike ball

                                                 how to make this spike ball ????????????

 take  a perfect square....

                                                    follow this process on opposite side
 such that we get the below picture

 now carefully see this picture.....try to fold as it is shown



don worry about the fold ,whether it is on right of left.....it
ll be corrected ...afterwards....

repeated the process on the opposite side....

 now flip the paper.....

 start from right side..
.n make sure that u follow the same process in your other modules

 repated the same on its opposite side..................................................>

                           make double fold or simply make the two outer fages half as shown above

         make half fold of the hole thing
 
    such that we get output as shown  below

 now.....most tricky part..............how to fix it........


 view it carefully.....in this way....first attach 5 modules...
which will form pentagon .....
negative spaces will forms triangles....
.in this way we will get desired outcome............

 for more help watch this video.....