I'm going to include exercises that I use with my students. The last one will be how to start a painting.
#1 VALUE - understanding lights and darks
The reason you need to know this is because to show dimension, create form and shadow, you will have to know how to make different values (lights and darks).
Example: This shows at least 5 different values, but notice the apple and vase only have two values at this point.
Materials: Black and white paint (either oil or acrylic), small canvas or any kind of surface even paper if you use acrylics (email me if you want the entire materials list that I give my students for the first 5 classes): firstname.lastname@example.org
Create your own value scale of 10 different values: Start with black, the lowest value, #1, keep adding white for the next eight spaces. The highest value will be #10, pure white.