Ah, I forgot talking about reading others' code. Reading good code is important. Understanding good design is important. I've read tons of Linux kernel code, so

Ah, I forgot talking about reading others' code. Reading good code is important. Understanding good design is important. I've read tons of Linux kernel code, source code of Linux packages, golang code in github, etc. Also, there are many books that discuss software design. The one that helped me most was "Principles of Computer System Design". Not all the parts are great, but reading the first few chapters & recommended books changed my software writing.