If you have AMS just use provided print profile
Swap Instructions (if you do not have AMS):
Start with black PLA Basic | Bambu Lab EU
At layer #6 (1.20mm) swap to Blue PLA Basic | Bambu Lab EU
At layer #8 (1.60mm) swap to Orange PLA Basic | Bambu Lab EU
At layer #11 (2.20mm) swap to Yellow PLA Basic | Bambu Lab EU
Experiment with other colors or use even more!
You can scale up and down but only X and Y. Z axis must remain the same as original