I bought one of these, much like the Dymo it prints on various sizes of heat shrink tubing, plus a bunch of other label materials/styles. So far I am happy with it.
https://www.bradyid.com/en-us/product/bmp21-plus

As to routing, this is my first airplane but not my first electrical rodeo as I've wired up data centers and radio sites for a long time. Use a schematic to know "switch A connects to light X terminal 1" or whatever, but it can also help to get an actual picture/drawing of your panel and a marker, and put lines where things need to go. This will help you decide where overlaps are going to happen, and plan the over/under accordingly, or even alter the routing to avoid it altogether. I'm also adding quick disconnects (Molex) in strategic locations to make maintenance/modification easier later on, since I expect the panel to be re-exposed at least a few more times before I get done fiddling with stuff.

Longer is better (you can trim), but don't go nuts here. Tefzel wire, especially the multi-conductor stuff, along with cable like RG400 can get really expensive. Pre-plan your connections and routing so that the buffer length is minimal.

colopilot wrote:I bought one of these, much like the Dymo it prints on various sizes of heat shrink tubing, plus a bunch of other label materials/styles. So far I am happy with it.
https://www.bradyid.com/en-us/product/bmp21-plus

As to routing, this is my first airplane but not my first electrical rodeo as I've wired up data centers and radio sites for a long time. Use a schematic to know "switch A connects to light X terminal 1" or whatever, but it can also help to get an actual picture/drawing of your panel and a marker, and put lines where things need to go. This will help you decide where overlaps are going to happen, and plan the over/under accordingly, or even alter the routing to avoid it altogether. I'm also adding quick disconnects (Molex) in strategic locations to make maintenance/modification easier later on, since I expect the panel to be re-exposed at least a few more times before I get done fiddling with stuff.

Longer is better (you can trim), but don't go nuts here. Tefzel wire, especially the multi-conductor stuff, along with cable like RG400 can get really expensive. Pre-plan your connections and routing so that the buffer length is minimal.

When I read this, it makes perfect sense and I agree with all of it. But damn, that's a lot of pre-planning

I did make a spreadsheet, listing every wire by number, circuit, to, from, gauge...
I've drawn up logic diagrams of how things connect (pencil and paper), which also helps keep things straight in my head.

The piece I didn't plan ahead of time was how these wires will bundle and what's the sequence to placing them. THAT takes a lot of forethought.

I did figure out this evening to keep a consistent pattern for wires entering a bundle from a bank of switches or breakers.
Inner most first. Right turns on top, left turns on bottom. Makes sense in my head and it keeps the wires flat in the bundle.

I'm sure I'll re-wire this panel three times before I'm happy.