I had a shoelace that was pretty well mangled, and didnt want to run out and buy a new pair. Granted they are usually pretty cheap, but I have a few hundred feet of 550 paracord at home and figured I'd make some quickly. I wanted to also have the stiff finished end (called an aglet) that wasn't just melted paracord. I decided to try heat-shrink tubing. Heat-shrink tubing is supposed to be for electrical connections, but it's incredibly handy for other things as well. The tubing generally comes in 3 sizes. I've seen small medium and large, in black, red, and white respectively. Your mileage may vary :)
27 to 72 inches of paracord for each lace (I made each of mine 60 inches, therefore needed 120 inches)
Automotive Heat shrink tubing, (about 1.5 inches per lace, for 2 laces, 3 inches)
Lighter or match
Step 1: Cut to Length
Cut the laces to the desired length. Sometimes the inner cords of the paracord will pull away from the cladding. Cut the end so that they are as flush as you can get them .