All parts are designed to be printed in the orientation they load into the slicer. You will likely need supports for the battery holder but maybe your bridging is up to the task.
Printing
The crystal should be printed in something translucent, I used natural PETG for mine. The LED holder should likewise be in something translucent or semi translucent, I used Printed Solid Jessie Quarter White for mine as it is good for lithophanes and diffuses light nicely. The rest of the parts don't matter what you use, mine are in Fusion Filaments Ionized Cobalt Black ABS.
I think using a translucent red PETG for the crystal and white LEDs would give a brighter crystal and obviously Flame Princess' crown is gold not black.
No real print settings requirements other than maybe make sure your seams on the crown are towards the rear. Nothing is particularly structural so 2-3 walls and something between 10-25% infill should be fine.
Assembly
I used four 5mm diameter red LEDs and powered them with two CR2032 batteries using this holder. They are wired up in two parallel sets of two LEDs in series with a 330ohm resistor on each set. These are the LEDs and resistors I used but really any should work.
LEDs are wired up and glued to the LED holder with hot glue. The battery pack is super glued to the Battery Holder and then that is super glued to the LED holder. The crystal is inserted into the front of the crown and then glued in place from the inside. Glue the led/battery assembly to the rear of the crown with super glue (or if printing in ABS then acetone welding works very nicely).
There are holes on the bottom of the crown which are designed to loop zip ties through so you can attach it to something like a headband or maybe a wig.
All parts were printed on my Voron 2.4.
The author marked this model as their own original creation.