Wiring Diagram is confusing...HELP!!!!

[WarpedMindGames]

I am a total newb when it comes to electronics and think I have jumped into the deep end, not knowing how to swim. I'm looking at the diagram attached , which is awesome btw, and can read it sorta well. My question is that I am seeing that some of the ground wires and power wires seem to come together or join up somewhere or go to 2 places ( see purple circles). I understand from the second diagram in the original post how to wire up the LED and the resistor for it, that is not my concern. What I am trying to determine For instance,When looking at the stepper motors, I see a ground coming out of the stepper controller (marked GND) then goes to a T junction (purple circle) that splits to the Y stepper motor ground AND the the DC PSU ground. Does this mean I route both wires to the same ground point? and if so, the other item i see that is confusing is that power line from the main switch goes to both the N (or terminal 2) on the DC PSU....AND....to the AC (terminal 2) on the laser PSU....how do I make this happen? I've looked at the original post where this diagram is published but was unable to come up with the answer.

I've gotten all the lines down that look like they have a single wire going from 1 terminal to the another, but the multiple wire thing is throwing me.....please help

[NickWL]

In an absolutely ideal world you would route all the ground wires to the same point (as is often done in HiFi I believe) but for most of us the chassis is grounded and can then be treated as a generalised ground available at any convenient point on it.
I have about four (maybe six?) ground terminals on my chassis (case), paint scrubbed off underneath them and the long bolt done up tight with two nuts. This means I can reach a handy grounding point from pretty well anywhere with just a few inches of wire.

[WarpedMindGames]

Thanks for your help on that! This solves the ground wire issue. How about the power wires in the circle on the right. Do I run 1 wire from the switch and send it to the DC PSU and then another power wire from that same terminal on the DC PSU over to the laser PSU or vice versa, or 2 wires from the main switch with each wire going to a PSU?

[NickWL]

It really doesn't make much difference but I think the tidier (and more future-proof) way would be to treat the two terminals on your power switch as the source of all power and run separate wires from these to anything requiring a 120v/240v supply.
Nick

[WarpedMindGames]

That sounds like a good plan, worst case scenario I'm replacing a $3.00 switch if it burns up and not the expensive electronics...thanks again for your help!

[NickWL]

I'd suggest that for this switch you use a big red cut-out button - when things go wrong and smoke starts happening (and it will) then a kill-switch is vital. And this is where it should be.
Marco sells them...
Nick

[WarpedMindGames]

I have one, it came with the upgrade kit.