(images via net-a-porter.com)
Tools and Materials:
Fabric dye (I used Rit Dye in Sunshine Orange)
Cut your jeans in to shorts, if you haven't already. Toss in the washer and dryer for a full cycle to not only get a better frayed edge, but to prep your jeans for their bath.
In an area where spills won't wreak too much havoc (like the bathtub, which could probably use a nice bleach cleaning anyway), fill your bucket with equal parts water and bleach, enough to fully submerge the shorts. Don't forget to open a window-- while the smell of chlorine is reminiscent of summer, it's not good for you!
Let soak for 10-30 minutes, but not too long, as the bleach will break down the fibers, making them weaker. I had some stubborn blue areas around the inseam, so I erred on the longer side.
It's a good idea to swish the shorts around in the bucket, so all areas of the fabric get sufficient contact with the liquid bleach. However, for your hands' sake, wear gloves or use a stick. If you do go bare-handed, don't make my mistake and wear your bracelets and rings. If you do, here's how to save your silver.
Rinse the shorts throughly with clean, cold water. Discard the bleach water. I ran mine in the washing machine to get rid of any leftover bleach, and let dry the shorts thoroughly.
For dying the shorts, follow the instructions that come with your fabric dye and work where messes are well-contained. I chose the bucket method in my building's utility sink-- I don't think apartment and communal living are well suited for doing this part in a bathtub. I also discarded leftover dye in a drain outside because I was worried about staining surfaces. By working carefully (for once), I was quite proud of myself for not making a gigantic mess, as is my usual MO.
My shorts soaked about 20 minutes, and I stirred using a spoon (metal so it wouldn't pick up the dye). Wearing gloves will keep you from getting Oompa-Loompa hands. Once the shorts rinsed clear (again, following package directions), I gave them one last wash/dry cycle.