Out of all the general mods out there, cable sleeving tests your patience and perseverance more than anything else. It does take a long time, so either plan to do cables one at a time or give yourself a weekend. The effort will pay off though as even the smallest amount of sleeving is a major addition to any custom computer rig.
Down the track we will revisit sleeving looking over some of the more advanced techniques like extending and cutting wires, soldering, crimping and lots of other tricks I just didn't have the room for this time in this guide.
Till then have fun with sleeving experiment with different color combinations, admire others hard work and develop your own techniques.
Hopefully I have inspired you to give sleeving a shot. Remember that there is no real right or wrong way to do it, so have a go - you may surprise yourself!