Tomas is distributing a PDF with the instructions, below is the opening text of the PDF. We like the closing four steps, they are at the end of this post:
The design is geodesic, based on the proper placement of pentagons and hexagons. Notice the pentagon 5 rows from the top of the balloon, where the lines converge:
The concept, described by Saraceno as "59 Steps To Be On Air By Sun Power," allows anyone to construct what he calls a "geodesic solar flying machine" using black polyethylene (the stuff used in garbage bags), a car radiator fan, a 12-volt battery, bicycle rims, tape, string, a child safety seat, and a bit of engineering savvy. The contraption is clearly not the safest idea for travel, but it appears that Saraceno's goal was to create a flying machine that puts environmental friendliness ahead of efficiency.
Tomas's site instructions: http://www.tomassaraceno.com/Projects/59Steps.html
Coverage from dvice: http://www.dvice.com/2013-2-1/solar-powered-balloon-lifts-you-sky-garbage-bags