There's a few ways of playing! You can check out everything on their website, here: https://recklessdeck.com/
But basically, there are a few "categories" to choose from, and you can draw one card from each. The cards you choose will tell you what to draw! (For example: One card says to draw A Victorian Frock Coat, and another says to draw a Staff or Wand.) I like to choose three or four and combine everything into one drawing! Makes for a more interesting piece!
Great for art block, lack of inspiration or you just want something random to draw.