Using thin tissue paper (so it will blow easily by the fan), create flame-like patterns using a combination of red, orange, and yellow markers and/or highlighters.
Cut an approximately 4-inch length of wooden skewer or dowel.
Glue flames to this section of skewer, leaving a short length of the skewer extending off to the right.
A short length of string (floss also works fine) can be used to yank the flames vertical when the dumpster lid opens.
Tie a knot in one end and, after passing the string through the center of the flames, use a dab of hot glue to affix the other end to the underside of the dumpster lid.
Attach a short extension made from a wooden skewer or something similar to the servo arm.
Press the servo arm onto the servo motor and check that its range of motion will allow the dumpster lid to open fully.
Use a thin strip of cardboard to keep the dumpster lid connected to the servo arm.
You may need to shave down the ends of the propellor for it to spin freely inside the dumpster bin.
Place the motor inside the dumpster and stick it in place using a small piece of double sided foam tape or a dab of hot glue.
Your wiring and electronics should fit neatly inside the dumpster, with the battery cable extending out the back.
When the lid on the right is lowered, the flames should be positioned right above the fan.
Poke the pushbutton switch from the battery cable out from under the front of the dumpster to create an easy on-off switch for your dumpster fire.