Print lying flat, no supports needed.
Looks best with multiple colors, but can of course be printed in a singel color.
Magnets should just press in place, but add a dab of super glue if you want. Magnet size: 10x3 mm.
How to program pause for filament change:
Cura: https://all3dp.com/2/cura-pause-at-height-how-to-do-it/
PrusaSlicer: https://help.prusa3d.com/article/insert-pause-or-custom-g-code-at-layer_120490
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Made with modified designs from freesvg.org
The author marked this model as their own original creation.