You don't need a steady hand to decorate a pot with attractive and modern geometric designs. Just a pot, tape, a few tools and lots of time and patience!
First of all, you have to figure the grid you will use to project your 2D design on the 3D pot. In the example, I used a grid composed by equilateral triangles. This is, a number of equidistant vertical lines crossed by diagonal lines at a 60 degree angle (A). This grid contains all the lines that will surround each colored shape of the design (B) and some extra lines that will be removed to reveal the final design (C).