The icosahedron is a platonic solid. Platonic solids are 3-dimensional shapes the sides of which (also known as 'faces') all have the same shape. The icosahedron has 20 faces, each a triangle. In the version I made, shown below, I stylized the icosahedron by curving the faces and adding an inner line. Read on to learn how to make this shape.
First start with this page and find 6 'spokes'.
Now continue with these instructions: (download the image to expand it in your photo viewer).