Help with connecting custom longmill to UNO + tb6600s

Hi,
I have been working on a Longmill from scratch and am done with the mechanical assembly. For the control board I have an arduino UNO with 4 tb6600s. I am unable to figure out manual wiring for the same through the provided longboard documentation because I don’t have a fair knowledge of PCBs. Is there anyone who has connected it or can help with manually wiring the longmill 4 motors to the stepper drivers and UNO? If so kindly guide.

When using GRBL, just google for “grbl pinout”. There are several pictures to identify the wiring.