While homemade mobiles aren’t certified, follow CPSC guidelines: no loose strings longer than 7 inches, and no small parts that could detach.

Dig a 6–12-inch base and line it with gravel or sand for drainage. The walls should be 12–18 inches high to contain flames.

Wear safety glasses and hearing protection, avoid pointing tools at yourself or others, and always depressurize hoses before disconnecting.