This is not a particularly elaborate chalk drawing showing just the Cutie Mark of Fluttershy (with the approaching Fluttershy Day 2019 of Equestria Daily) in mind.  
The reason I am still posting this is that it was a bit of a test run. I didn’t really draw this but rather sprayed it with a mixture of water and chalk powder, using a mask I had cut from corrugated card board.When I first sprayed it it looked like it wouldn’t really work with the colors barely visible at all. However, once the water dried up the color turned up and the result of the test was better than I had expected. I may create some more elaborate spraying masks for future projects as they would allow to create chalk images faster and with very smooth surfaces.