Mixing media however, does take understanding of them. Some media mix readily, others do not. In order to know, you have to experiment with them. it is not enough to simply read about them and follow the rules. Acrylics under oils, don’t mix colored pencil and graphite. You need to understand why and what are the results. Sometimes these bad results are exactly what you want! So playing with art and art materials are an essential part of art education.