This is a photo of the underpainting. Done in Burnt Sienna, this is how I place my image on the panel, develop the pattern of values and make sure I like the composition.
Here I have begun to weave the background of leaves that the branch I am focusing on is nestled into.
Here I have spent several sessions on the acorns and leaves in the foreground. Several more are required to finish the detail of the subject, and to balance it with the background.
The finished painting is found at the top of the post.