Every line has to come from somewhere and go somewhere. This requires carving, or pushing paint around. It is impossible to be perfect, but with time and layers, it is possible to create an illusion.
Choose a line that matters. I chose the under the tail line pictured below.
Paint it
Take another brush and either with terpenoid or paint, chisel it over to be a better representation of what you see.
Notice if the line changes color as it bends.
Make it so.
Here’s my in-progress pictures: