Step 1: Tools and Materials
- Four plastic shopping bags
-Shoelace or string
Step 2: Welding the Plastic Sheets
2. Take one bag and fold it "hamburger style" so that it makes roughly a square. Sandwich it in between two layers of parchment paper and iron it. The time and temperature will vary, but it's better to start slow. The bag should burn or melt, just lightly fuse together. When you think you're done, roll the sheet between your fingers. If you feel it separate, iron a bit longer.
3. Take your second bag and fold it over the welded sheet so there is fresh plastic covering both sides. Place it between parchment paper and iron it until it is an even 4-ply sheet.
4. Repeat with the last two bags, this time folding "hot dog style."
5. When you're done, you should have two 4-ply sheets, one long and skinny and the other roughly square. Trim off the edges.
Step 3: Taking Shape
2. Cut out the shape, leaving an additional 1/4" outside of the line for a seam.
3. Iron the seat shape one more time to seal the edges.