Faran Krentcil guides us:
Step 1 Gather your thorns.
"Take three roses and slice off their thorns with gardening shears. Be very careful, or you will bleed."
Step 2 Paint each thorn.
"Paint each thorn a blood red, or whatever color you'll use for your manicure (though aside from red, we think black is the only other hue that would work)."
Step 3 Paint your nails.
"Paint your nails the same shade."
Step 4 Glue each thorn.
"Take your nail polish and slick the bottom of the thorns with the brush, using it as "glue" for each thorn to stick on each nail."
Step 5 Let it dry.
"Wait for it to dry (about 20 minutes). Obviously, you'll have to be cautious when flaunting this sharp new look (and we'd only recommend it for something very special and relatively brief - you don't want thorns on your hands all day)."