The fact is, that I am not a beginner in color theory, but I think that it is always good to remind myself. And it was a good idea. Gouache is a new medium for me; understanding how the pigments work helped me a lot. The class was fun to do and I made my understanding of colors even stronger thanks to this. 
At first, I just played with the colors. Trying how the mixing of different types of pigments works. 
For the final work, I did 3 different versions of the same illustration. One with just cool pigment, the second with warm pigment, and the third just with the two complementary colors.