Ripping an old pair of jeans or transforming them into shorts is probably the most widespread DIY. Almost everybody has ever done something like this, including those who think they are not skilled enough. But the challenge now is to go beyond broken and frayed...
Studs are one of the easiest DIY options, as simple as hammering them into the fabric and bending the barbs inward. Most spikes can be applied with screws, but some require a professional rivet machine.
Scalloped: Chloé brought the scalloped back to catwalks a few years ago. I am a such big fan of this effect. Page Sixsixsix makes her interpretation of this trend on denim. You'll just need scissors and a pattern you can easily make with cardboard. Pixie in Pumps does the same process and adds a subtle dip-dye.
I'm in love with the shorts from the picture on the left, and they're quite easy to make. The other option is covering the front with some printed fabric or lace.
Finally, the paint! which is always my favorite DIY ingredient. You can use a stencil, thin brushes for small drawings, or just let some paint drops fall randomly onto your shorts. I think that the shorts from the pictures on the left were made using bleach and textile dye.
Elena from Desde Tenerife Con Amor did an awesome DIY inspired by Sass & Bide. Take a look at her tutorial, I absolutely love the result.
DIY por Desde Tenerife con Amor vs. Sass & BideTake a look at my DIY Shopping Guide to know where to find all the stuff you need for your projects.