Here are tips to reduce filament waste when using multimaterial FDM printers. I am using the Bambu Labs X1 Carbon (of course!) but these tips will apply to any printer capable of single nozzle multimaterial FDM 3D printing.

Tips:
1:33 editor's note: reduce model height
1:54 Print big models.
2:17 Increase layer height.
2:35 Print small multicolor models in bulk.
2:53 Break your model apart if possible.
3:11 Find the ideal flush volume for your filaments.
3:31 Group models needing the same exact colors together.
3:53 Use sequential printing.
4:32 printing my Rhino Mech Unit (~80% filament efficiency)
6:15 assembling my Rhino Mech Unit

Rhino Mech Unit TPU version:
https://exsurgemp.gumroad.com/l/sazzg