I find it beneficial to do a line drawing study, as the first step, when I have a new subject. This is especially true when I am working with birds. The drawing study gives me an opportunity to focus on their shape and proportion along with portraying their unique characteristics. Here are a group of bird drawing studies. The top image is a Blue-Gray Gnatcatcher, below includes the male Cardinal, the male Pine Warbler, and the male Goldfinch.