There are two things, that really help you to improve your skills: PRACTICE and RELEASE OFTEN
Creating something with a given theme and a meaningful deadline really helps me to stay focused and get something done to showcase. It’s not about creating a perfect portfolio piece but to concentrate on one idea and extend on what I have learned before. That’s why these weekly showcase challenges over at the Blender Community forum really kick-started my modeling and post processing pipeline skills.
Blog posts referring to my Blender Practice Challenges
Find more pictures and 3D Sketchfab models inside these weekly posts:
(sorry, going to catch up and post the older challenges aswell ;_; )