What would you do if you could be invisible for one day?
The idea itself is good, but if you want to open a productive English discussion, remember to use the correct grammar. This phrasing is taught at A2/B1 level. By using "disappeared", you asked quite a different question.
So what would I do? Fight crime, right wrongs, get up to mischief? Would I have the energy and inclination for all that? :)
Almost everyday in dreams I used to see my self turn into transparent girl and I always go back into my home, take my clothes, papers, books, and take a very deep breath then go back to be a refugee again.
But in real life I will go to the airport and climb into the plane and travel into Turkey.