Build things you want to use. Or build things other people want to use. Do practice problems online (LeetCode, Project Euler, etc.). Read more documentation.
Pick a tech stack that you want to become an expert on (preferably an employable one), and start learning. Buy the books.
It sounds like you're feeling a lack of confidence in your knowledge and abilities, and the only way to improve those is to continue learning and improving.
One other consideration is: do you spend a significant amount of time on repeated processes? Perhaps during development you're 1) logging into your database, 2) dropping some tables, 3) re-running some tests that populate the database, 4) viewing the results. Can you automate such processes? Can you put together a few scripts or utilities that make you more efficient? Can you find boilerplate or scaffolding that gets you 20-30% of the way there rather than starting from scratch?