Among the skills and techniques you need to acquire for pastel painting are an feeling for how the pastel is going to behave on the paper, an understanding of how different tints work with each other, and most importantly, an innate understanding of color.
The most common mistake people make when starting out with pastels is to buy too many sticks and too many different colors. What you need to do is limit your selection to a range of warm and cool colors from each of the primaries and secondaries, plus a few browns (earth colors), a black, and a white.
Putting your own selection together is better than buying a ready-made set of pastels as this way you buy only what you need. Look at what is available either at your local art store or an online art supplies store, and let your subconscious select one example of each of the primaries and secondaries. (See Putting Your Own Set of Pastel Colors Together for suggested colors.)
You will also need to get a few light and dark versions of these colors to give you a range of painting tones. The ideal is to have three different tones across the colors (light, mid, and dark), but some, like yellow, only really come in light- and mid-tones.
