200-Pack RJ45 Cat6 Pass Through Connector RJ45 Modular Plugs for Solid or Stranded UTP Cable

Get this from Klein and these style connectors. You just need to remove the outer jacket, un-strand the wires, and feed them through the connector in the correct order, then crimp and snip the excess off. I used to do it by straightening all the wires and smoothing them out and carefully making sure they lined up, then cutting them to about a half inch, then feeding them into the traditional connector and crimping and crossing my fingers it all worked when I tested it with the test tool. 90% of the time it did, the other 10% I had to yell fuck, and cut the end off and try again. Each time the cable got shorter and shorter so I always made them too longer to have a bunch of slack in case I fucked up.