I initially took a lot of evening classes at a local university, drawing and painting human models, still lifes and portraits, in addition to my weekend plein air class outdoors. I painted with pastels and watercolors, in addition to oils. You draw with pastels and there is no color mixing. It is very immediate, and the myriad colors are lovely. Watercolor is trickier and less forgiving. You have to start with the light colors first and slowly go darker. You can’t change dark colors once they are laid and you also need to leave white spaces. This is just the opposite of oils, where you start with your dark values first, and you can paint over your mistakes.
I slowly worked up to using my oils more and more over time. One of the best learning experiences with oils was participating in the 30 Days-30 Paintings Challenge by artist Leslie Saeta. Painting every day improved my technique much more rapidly. Oils are less fragile than either pastels or watercolors and are less expensive to frame: no matting or glass is required. So, I decided to focus on oils. However, I still like to sketch with watercolors when I travel. I can carry everything I need in a small bag.