Magic Paper Toy / Kaleidocycle Tutorial

You'll need cutting mat, knife and ruler - or just sharp scissors. And quick drying paper glue.
Cut out the design very precisely.
Gently score/trace (this will make folding precise and easy) all the diagonal lines...
...as well as the vertical lines. If not the tip of a knife, then a needle or a very pointy pair of scissors will work for this.
Fold and bend the design into a tube like form - like this.
When it is folded into shape, it is a kind of angular snake...
.....where you need to glue the overlapping triangles, like this. Do them one at a time.
Last detail is to put the end flaps into the tail, to close the kaleidocycle. Hold on until completely dry - and then play!