Be very careful.
The best way to go about it is take two steppers side by side both plugged in then simply write down the wire order
say for example pin 1-red 2-yellow so on the other one 1-grey 2-green
That will at least let you know the order of those particular steppers.
On the diagram blow it up and print it if you can and mark down what colors you have for what pins they go to.
one thing to note is there is NO WIRING STANDARD they can be any color, what matters is what pins they need to go in, I've seen Hot green and white wires!
It's a real PITA I know, took me a solid half hour to splice the Y motors just so the first time was the last time.
When you first activate a stepper, cover the power switch and be ready if you hear buzzing, instead of movement, DO NOT unplug a stepper on a powered on machine.