EddieJ: You can look at these C tutorials:
Practice, pick up a text/learning book from the library and just practice at it.
Do things you want to try, read something in a book and try it.
Then come up with a program that you would like to have out there and make it.
Hub4Tech offers online free tutorials for more info- goo.gl/lXjp8t
By studying, reading & practicing. If you have formal schooling, that would not hurt!