The first step I took was to find hollow balls which could be filled with the electronics for movement, sounds and lights. I did not want to go with the “classic” approach of gluing several layers of paper on a beach ball as it seemed to complex and not too perfect in the end.
I was looking for paper/carton balls but could not find anything in the size I wanted (at least 30cm for the body) but I eventually stumbled upon a styrofoam balls. I bought 30cm ball for the body and 20cm for the head (I really don’t like naming it a “dome” for some weird reason). I am fully aware that the original relation is not perfect (as the head should be some 17-18cm) but I hope it is going to be fine enough in the end.
The same shop I was ordering the styrofoam balls had also wonderful 60mm transparent christmas tree balls so I did not have to think twice to order one to be used as the big “radar eye”.
I browsed the store and also found a nice round holder which will be used to keep the final BB-8 in place when not in use.
I already had saved a wooden stick a while ago (it was element of a washing machine package – I knew I could use it one day!) and I will use it as the base “core” of the internal mechanisms by attaching all the electronics, batteries and engines to it.