Besides some of the very, very obvious (don’t copy/paste 100 lines of code, make it a function! Write comments for your future self who has forgotten this codebase 3 years from now!), I’m not sure how to write clean, efficient code that follows good practices.
In other words, I’m always privating my repos because I’m not sure if I’m doing some horrible beginner inefficiency/bad practice where I should be embarrassed for having written it, let alone for letting other people see it. Aside from https://refactoring.guru, where should I be learning and what should I be learning?
Someone said it before: write for test-ability. I find that code which is easier to test, is easier to read.
Also, use a linter and a code formatter. Those can be used from the get-go. They cost little and will allow you to write code without thinking too much about what it looks like.
What more, I can recommend letting the code rest for a while after having written it (1 week or more), then try to read it again and see how well you understand your own code. You’ll notice things like variable names being confusing, function names being non-descript or missing documentation, methods being too long, code branching too much, and so on.
And finally, ask for people to review the part of your code you are unsatisfied with. https://programming.dev/c/code_review isn’t very active, but I check it sometimes and try to give advice when I can.
