Pretty easy:
1. I would cover myself in oil. Since oil flows on water I would float up and escape for a bit.
2. I would order as many bouncy castles as I can.
Context: In the 17th century, bouncy castles were filled with air. Nowadays they are filled with Lays bags, since they have a higher amount of air.
3. I would get the Lays bags out of the bouncy castles and throw them in the ocean.
4. The whale would choke on the plastic.