PET is Polyethylene Terephthalate, which is a thermoplastic polymer.
It can be re formed by heating. After heating process, it becomes more stiff, rigid, durable and glassy. It becomes even stronger and crystallized when perforated.
This re formed and perforated second life as a bowl is longer and the original bottle.
Object now has an artistic value other than serving as a container for almost any material (eggs, bread, nuts, pencils, soaps, small objects etc.), it can be used as an ideal fruit bowl as the air circulation prevents fruit decay.
Step 1: what you need?
Bottle, cutter or scissors, soldering iron, flame (I use a spirit burner which I made with a jar and cotton cord)