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Don't print the humanoid first. Print one joint. Hackaday filed Berkeley Humanoid Lite on 30 August. Donald Papp's headline was "Low(er)-Cost Humanoid Robot Leverages DIY Actuators." The useful object on that page isn't a finished person-shaped product. It's a 3D-printed cycloidal joint you can make on a desktop printer before you decide whether you want a robot at all.

Exploded diagram of a cycloidal drive showing its gear parts — Exploded cycloidal drive. Public-domain diagram, Wikimedia Commons.

Step by step

Prepare the encoder
Swap the resistors on the AS5600 board as the Berkeley Humanoid Lite gitbook shows, then solder VCC, GND, SDA and SCL on the matching pads.
Fit the magnet
Hot-glue the magnet that came with the encoder to the rotor shaft. It's radially charged, and a hardware-store disc magnet won't work.
Print and assemble
Print the housing, cycloidal disks, input shaft and output shaft in PLA on a 200 mm build volume, then assemble them following the lab's video and Figure 4 of the paper.
Solder the electronics
Connect the encoder and motor to the B-G431B-ESC1 with care, because the CAN pads lift easily. Use the lab's colour code for the 14 AWG power and 30 AWG CAN wires.
Test at 24 volts
Run the joint on a 24 V rail, the same as the paper. Check it turns, holds a position and doesn't strip a printed disk before you open the full robot bill.