I've been seeing coloured sand all over the internet (ie pinterest) but not in any stores so I decided to try and make my own. A lot of food colourant (and a pair of very colourful hands) later and voila! I had to wait for the sand to dry out first, I poured the green sand, transplanted the plant with its potting soil from its original pot, and then poured the red sand around it. I watered it a little by carefully aiming the water at the ground in the middle. I'm curious to see if it will work out, but with the ground around it's roots I have high hopes. I've been known to overwater my succulents though, I'm still trying to find the happy middleground.
Well done! It looks lovely. I do hope the colour will hold for a while. I'm no good with cacti or succulents either.
Oh, how pretty, I hope it stays healthy for you. If it starts suffering you might re-do the planting and leave the cacti in a pot of soil, just bury it in the sand to hide the pot.