I wanted a guitar cable that was a bit different, and wanted to do it myself, but found the options for good-looking cable sleeving were few, especially if it was to feel nice as well as look good. It's been a bit of an epic to get this one done, but from what I've learnt the next few should be straight forward!

Supplies

Materials:

Cable - Van Damme Unbalanced Pro Patch LITE

Sleeving - Hollow PPM Cord, 8mm diameter "Bubble Gum"

2x Jack plugs - Neutrik NP2RX-B

2x Oversize Chuck/Boot - Neutrik BPX-L

Tools and consumables:

Soldering Iron - Ideally 40W+

Old straight Jack plug (metal body, not plastic!)

Cigarette lighter

Hot air gun

Sharp Scissors

Scalpel/Stanley knife (or your preferred tools for stripping cable)

Solder

Heatshrink that will just go over the paracord + cable (not the type with hot melt glue lining)

Step 1: Tips

Make sure to read to the end before attempting this - I learnt a few things along the way that showed that my original choice of materials was not suitable (it won't require great observation skills to note that the sleeving and cable change during the instructable!):

The bunching/releasing caterpillar motion required to inch the cable through the sleeving can also inch the core wire/insulator through the braided screen/outer insulator, resulting in the core protruding from the outer at the end being pushed through the sleeving, as shown in the first pic. This got caught up in the fibres in the paracord, making a short length of it unusable. This may be avoidable with more gentle inching, but for this instance, I just "sharpened" the other end of the cable (second picture), removed some strands of screen braid that were protruding, and pushed that end through in the next attempt.
The next issue I found was that the "clutch" assembly from the Neutrik plug wouldn't fit over both the paracord and cable. The first cable type was some Cordial CIK122 I had lying around, which has a nominal jacket diameter of 6.1mm. My finished cable ended up with Van Damme Pro Patch cable, which has a diameter of 4.65mm (linked in the materials list).
The Neutrik plug is easier to solder if all connections (plug and cable) are pre-tinned.

Step 2: Prepare the Paracord

You will probably find that the paracord as supplied has had its ends singed to reduce fraying (first pic). It will likely not have been left in a way that makes pushing cable through easy.

Cut off one melted end with scissors and put the 'old straight jack plug' in this end to spread the fibres, making a small funnel, being careful not to let the end fray too much. Singe the fibres with the cigarette lighter or a small hot air gun to stop it fraying when we push the cable through (second pic).

Step 3: Push the Cable Through the Paracord

Make sure the end of the cable that is to be pushed through has no stray wire strands, as they will snag on the paracord and make it much more difficult to push through.

Push the cable through the paracord from the end we've just funnelled, carefully bunching up the paracord like it's some sort of monster leech swallowing the cable whole (bunching just visible in the pic).

Once the sleeving gets to the other end of the cable, pull it tight over the cable by holding the end you just got to and pulling it back toward the other end. Cut the sleeving off at that end to match the length of the cable, and singe it again to stop it unravelling

Step 4: Neatening Up

Put short (1") lengths of heat shrink tubing over the ends of the paracord and careful hot air gun to shape the ends to be smooth and tight around the cable. Carefully cut off the heatshrink without damaging the paracord as the Neutrik chuck assembly won't fit over the heatshrink.

Step 5: Fit the Connector Boots

Fit the Neutrik boot over the paracord (it may help to wrap a small amount of masking tape over the paracord/cable end to hold it together - remove the tape once the boot is on).

Step 6: Solder the Plugs

Prepare the ends of the cable as per the Neutrik assembly guide (on their website) and solder on the plug. Note the black layer is not the insulator around the central conductor, but is a conductive layer intended to reduce handling noise - if your cable has this it needs stripping back away from the conductor.

Step 7: Assemble the Plugs

Ease the clutch over the paracord, ensuring a good amount of the paracord is being gripped, and finish assembling the plug, being careful when fitting the boot that the paracord doesn't get all bunched up in front of it, which will stop you from tightening it sufficiently. Also watch out for cross-threading the boot into the plug body, which is easier to do when it's a tight fit!