I've found that controlling the "rat's nest" is best to start with the little individual 12V wires. I bought some inexpensive shrink tubing in different sizes. I "fold" the excess wire lead and slip a piece of shrink tube around each little bundle. This is better than trying to cut wires to the proper length. If you move something, just add or remove what you need from the tube. Since you're not shrinking the wrap, you can always salvage it for future use. This really helps clean up the wire mess. For larger DC wires or for AC wires, I use tea-cup hooks under the desk. Just slip the wires into the cup hooks. For larger or multiple AC wires, I run them through shower curtain hooks and hang them on the tea-cup hooks. All wires off the floor and mostly out of sight. Good luck!