Learn about what you must think before making an interface. Tools to make mock-ups are also listed here.
UML is a tool used to work on the conception part of a project.
Make a projectread
What's a project in real-life and how one should handle it.
Make Git projectread
A gathering of everything related to Git projects and their management.
A project framework/methodology following the Agile mindset.
Because writing code can be easier, and you would rather want to learn the good practices beforehand.
What are tests and assertions? What's the Test-driven development and the Behavior-driven development?
What are the best practices when writing code? KISS, YAGNI, SOLID, DRY, and a lot more!
Learn more about methods like model-driven dev, data-driven...