[borlanco]

That's easy. After learning the language, study good C code. Try to grok how the masters build higher-level abstractions.

Learn from widely used C code that is not a toy. Examples: sqlite.org, git-scm.org

If you don't understand something, look it up in the C standard doc.

Most of the time, you will want to program for speed, and C will let you. Learn and practice C profiling.

Also, you will need to learn defensive programming. The best source about this is "Learn C The Hard Way" by Zed Shaw: https://github.com/zedshaw/learn-c-the-hard-way-lectures