I'm just going to start off by saying that this project wasn't as simple as I thought:
To plant these things, you have to touch them...
After several attempts bare-handed, I used my coated fillet gloves (made for fishing) to plant & it seemed to help, but I still ended up picking spines out of my hands when the job was finished.
Using a small bag of cactus/succulent potting soil mix, I planted a variety of cacti & succulents in an old galvanized trough feeder. I topped off the soil with gold decorative rocks & scattered various other stones & brooches throughout. It was worth every prick.