The assembling of the CX-I extruders on sigma and non-sigma profiles is explained here. The assembling can be achieved qucikly for sigma profiles with specially designed metal sheets. And for non-sigma profiles you can use some printable parts to achieve assembling.
Remove the three screws on top of the CX-I extruder from the box and detach it from the motor.
Place the metal sheet that comes in the box between the motor and the extruder. (The motor socket should face you, the lever should be on the left side, and the longer side of the metal sheet should be at the front).
After tightening the screws, the assembling will be done.
Use the bolt and nut that come in the box to secure the CX-I extruders to your printer.
Remove the three screws on top of the CX-I extruder from the box and detach it from the motor.
Place the printed extruder holder between the extruders with the motor underneath. (The motor socket should face you, and the extruder lever should be on the left side during installation)
Tighten the screws.
Attach the printable handles to the extruder holder.
You can mount the extruder holder to your printer now.
You can access the printable parts for non-sigma printers from here.
Also, filament holders is needed to print multicolor. You can buy from Here!