First of all, we custom-make a empty wooden box without head cover and bottom and carve it by hammer and knife. In order to separate our dark box into different independent grids, we make a 16 cells barrier by 6 tagboards' assembly. Then we need a head cover which has 48 holes matched with the barrier so that we can insert 3 test tubes into each cell. Last we should weld small electronic components onto our PCB and revise them so that they can output linear light under linear electric current. 800px Thus we have all of our assembly parts well prepared!