Here is the wiring diagram. Depending on your definition of "forward" and "backward" or "up" and "down" - your steppers may end up going the "wrong way". The best choice is to see if you CAM software can invert the outputs. Or you can swap the stepper windings. It's not obvious what to do, if you need to know, drop me a line and I'll draw the "swapped" version.
The nature of this type of project is that it goes together - and it comes apart. Often. So I used connectors (from Jameco) that had enough pins (9) and sufficient current carrying capacity. Get at least one M and one F for each motor, you need to order the individual pins and sockets a-la-carte. Get an extraction tool also. If you have the extra $, the proper crimping tool would be nice too.
Here's the Y-Axis motor showing the 9-pin Molex connector. I opted for the 9-pin connector vs. a 6-pin as I am planning to run my limit and/or home switches through the same connector.