Last week, I tried different ways of manufacturing balloon. And it turned out the soldering iron way is the best way for one person to do that in the lab.
Last Friday, I successfully manufactured one in the lab, as shown in the following figures.
And the following figure is what happened after 4 hours:
So I spend whole weekend on making a bigger fish oval-shape balloon. The result is as follows, which is pretty nice:
The timelapse video of how I setup this by only one person (since I the only one in the FORAY team to be allowed in the lab)