Only add the eyes, lips, and wrinkles after the planes are correct. Details on a bad structure are just fancy mistakes.
A dedicated workspace with a protective mat and a small container of water (for smoothing) is key. Polymer Clay Tools for Beginners - Jessama Tutorials
Exercise: Block out three 1-minute gesture poses in clay (30–60 minute session).
Thick aluminum or copper wire provides the skeleton that prevents your character from collapsing. Step-by-Step Sculpting Process