Learn by doing.
Series on front-end web development, software design, and the tools that tie them together. Each one is multi-chapter and designed to be read start to finish.
The chapters build on each other, but each one is also a self-contained tutorial. Jump in wherever you need to, or start at chapter one and work through.
Prerequisites: access to a computer running a Unix-like OS (Linux or macOS), a command prompt, a web browser.
Front-End Fundamentals
Building a WordPress Theme from Scratch
Start at the command line. Finish with a hand-built WordPress theme and plugin. 18 chapters, no shortcuts.
Start with Ch. 01