Does anyone know how to increase the height of these types of office chairs? The height of this office chair is at the lowest and I can't find a tutorial to uplift it. Help!

This chair has two handles-the handle with a round head can be moved out and in and "locks" the chair, I guess.the other handle with the flat head moves 90 degree downwards. The sellers had shown us how to lift the seat of the chair but I forgot, now I'm desperate to learn how to increase its height since it's too low. http://ift.tt/2pbeBey via /r/DIY http://ift.tt/2IplbXy