Here are three tried-and-true classics to guide you on your way to becoming a better writer:
Ernest Hemingway on Writing
by Larry W. Phillips (Editor)
A collection of Hemingway’s writings on writing.
On Writing Well, 30th Anniversary Edition: The Classic Guide to Writing Nonfiction
by William K. Zinsser (Author)
Simplicity is key.
The Elements of Style, Fourth Edition
by William Strunk Jr. (Author), E. B. White (Author),
Of course, constant practice and a good editor are invaluable.
Now, go off and read and write well.