I had a simple orange frame that I decide to turn into an Evil frame. You can see the work is already in progress. I bought a pack of modeling paste and begin to work.
Make a nipple look like thorn
Place it on a frame where you want your thorn to be
Then rind it. I use my finger nails for it. Make as many thorns as you want. this is the first attempt to create frames with modeling paste. I'll try something more elegant next time.
The finished frame. Now I just have to wait for it to dry. I'll paint it in black later and add some polish. I'll post the finished product photo as soon as it will dry ;)